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President Bush and members of his administration on Tuesday were defending the president's border security proposal, saying they have enough resources to put National Guard troops at the border and to enforce other immigration reforms.

"The program to put guards on the border is one that will enable the Border Patrol to do its job better. It's very important for the American people because it's the Border Patrol that's going to be on the front line of apprehending people trying to sneak into our country," Bush said during an appearance with Australian Prime Minister John Howard.

Bush said that his proposal to place up to 6,000 Guard members along the southern U.S. border "really is not going to put a strain on our capacity to fight and win a War on Terror as well as deal with natural disasters."

He said the administration would be working with governors to make sure the deployment doesn't have a negative impact on their ability to deal with storms or other emergencies. The states also will be eligible for federal reimbursement for use of National Guard forces.

Bush renewed his call for a temporary worker program that runs in conjunction with tighter border security, which he says must happen together for immigration reform to be effective.

"The objective is, on the one hand, protect our borders, and on the other hand, never lose sight of the thing that makes America unique, which is we're a land of immigrants. ... We're not going to discriminate against people," Bush said.

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In a nationally televised speech Monday, Bush called for up to 6,000 National Guard troops to be deployed to the southern U.S. border and for Congress to pass a guest worker plan. He stressed that the United States is not militarizing its southern border and that the Guardsmen will not serve in a law enforcement capacity.

Bush will visit the U.S.-Mexico border in Yuma, Ariz., on Thursday to continue to press for his proposal.

The Guardsmen would mostly serve two-week stints before rotating out of the assignment, so keeping the force level at 6,000 over the course of a year could require up to 156,000 troops.

The troops would be paid for with some of the $1.9 billion requested from Congress to supplement border enforcement this year. Senate Armed Services Committee Chairman John Warner, R-Va., said he intends to call a hearing on the National Guard deployment "at the earliest possible opportunity."

Bush also said he would ask Congress for additional funding and legal authority to end "catch and release."

"We have expanded the number of beds in our detention facilities, and we will continue to add more. We have expedited the legal process to cut the average deportation time. And we are making it clear to foreign governments that they must accept back their citizens who violate our immigration laws," Bush said during his Monday night address.

Homeland Security Secretary Michael Chertoff and other officials on Tuesday also joined the president's call.

"What the president did last night is to put on the turbo chargers in dealing with this focused, anti-illegal immigrant effort that we've got, on a comprehensive basis," Chertoff said during a press conference in Washington. "And if we take advantage of this, and we move comprehensively in Congress to build the entire program ... we can have a transformative effect on the immigration problem — the illegal immigration problem — that has plagued our country for over 20 years."

Chertoff said that while the bulk of immigrants are still coming from Mexico, new methods to end the derided "catch and release" program seem to be working with illegal immigrants coming over the border from other countries. "Catch and release" is when illegals are arrested, processed, then let go on the promise they will return for a court appearance at a later date. Many never show up in court.

"We're actually seeing, for the first time, a seasonal decrease in the number of people from these countries," Chertoff said.

Senate Gets Down to Business

Meanwhile, the Senate cast its first votes on the immigration bill, rejecting a call to secure the nation's borders before tackling other immigration-related concerns.

The vote was 55-40 against a proposal by Sen. Johnny Isakson, R-Ga., who said that anything less than a border security-first approach amounted to "a wink and a nod one more time to those who would come here" unlawfully.

Opponents of the current Senate package said demonstration of support for Isakson's amendment could throw a wrench into the plans for the bill's supporters. Thirty-three Republicans and seven Democrats voted in favor of Isakson's amendment."A solid vote for Isakson means it's an idea that will very much be considered in conference," said Sen. Kay Bailey Hutchison, R-Texas, referring to the conference committee that will have to come to agreement over any differences between the House bill and the Senate bill when it's complete.

Republican and Democratic supporters of the sweeping Senate bill said Isakson's approach would be self-defeating and derail the approach that Bush backed in Monday night's speech from the Oval Office. "We have to have a comprehensive approach if we're going to gain control of the borders," said Sen. Edward M. Kennedy, D-Mass.

In a second vote, the Senate agreed 79-16 to an amendment by Sen. Ken Salazar, D-Colo., that says prior to implementation of any guest worker program, the onus is on the president to determine whether or not the implementation of the program would strengthen U.S. national security. Such a determination would trigger the guest worker program.

Leaders have predicted that the Senate will produce a final bill by the end of the month, which would then need to be hashed out with the House version.

Senate Majority Leader Bill Frist told reporters that he believes Republicans will end up supporting a comprehensive plan like the president wants including measures not in the House bill passed in December: "The temporary worker program, stopping the hemorrhaging at the border, employer workplace enforcement, and addressing 12 million people here."

"A majority of the caucus will support the comprehensive approach," Frist, of Tennessee, said. "I can't tell you what the vote would be right now, but I do believe real progress has been made."

But Democrats too have been split in the Senate on the issue a guest worker program. Sen. Byron Dorgan, D-N.D., offered an amendment that would have seriously curtailed the guest worker program.

"The so-called guest provision here are people who will come here and then they will apply for a green card and then they will stay here. there's nothing temporary about that. don't call them guests," Dorgan said Tuesday on the Senate floor.

Dorgan's proposal was struck down by a 69-28 vote, but a Democratic rift was apparent with 22 Democrats voting against Dorgan, and 21 voting in favor of limiting the guest worker program. Only seven Republicans voted with Dorgan, and 46 Republicans rallied behind Judiciary Committee Chairman Arlen Specter, who pushed for protecting the guest worker provision.

Late Tuesday, the Senate voted to cut the number of guest worker visas approved in the first year of that program from 325,000 to 200,000, marking the first substantive change in the bipartisan immigration reform bill since debate began in earnest on Monday.

The amendment, sponsored by New Mexico Democratic Sen. Jeff Bingaman, survived an effort to kill it on a 79-18 vote. The Senate then approved the Bingaman amendment by a voice vote. This is the first major alteration of the base Senate bill and a clear indication the Senate was uncomfortable with the size of the guest worker program as originally drafted by Sens. John McCain of Arizona and Edward Kennedy of Massachusetts, the bill's principal co-sponsors. Democrats fear guest workers will drive down the wages of U.S. workers. Labor unions also opposed the original size of the guest worker program. The Senate vote to cut it nearly in half.

Ready to Roll

Federal officials say they are ready to get started whenever authority is given to them.

"We can certainly do what is being asked by our commander in chief," Army Lt. Gen. Steven Blum, National Guard bureau chief, said at Tuesday's press conference alongside Chertoff.

"This is going to be a tremendous enforcement support partnership," added U.S. Border Patrol chief David Aguilar.

Julie Myers, assistant secretary for the Department of Homeland Security's Immigration and Customs Enforcement, announced Monday that DHS would expand the "Expedited Removal" process to deport illegal alien families apprehended in areas along the nation's borders. A new 500-bed facility opened Monday in Williamson County, Texas, to house illegal alien families together.

The officials said the new troop movements would in part be modeled after anti-drug operations already in place along the border, a demonstration that the government already has the capacity to undertake.

Chertoff said the ramp-up will begin in June, but won't take place all in one lump.

"Bear in mind it's not going to happen simultaneously, and we're not going to put 6,000 National Guard on the border in one day. But the process should begin in June," Chertoff said.

It's not clear exactly how the troop forces will be divvied up just yet, and the officials said they did not yet know how much the new troop movement would cost. It will be up to individual border state governors to decide how to use their Guard forces, and Blum said the cost estimates will be clearer later this week.

Assistant Secretary of Defense for Homeland Defense Paul McHale said Guard members are already on active duty along the border with Mexico — 400 as of Monday — assisting counter-drug activities.

McHale said the new force commitments were "much more robust" in terms of personnel and resources, but are not wholly different than what the government has been doing for nearly two decades.

"We're going to be doing what we have done in the past but on a much larger scale and more effectively in order to provide a transition to improve civilian capabilities a little bit further down the line," McHale said.

In his Monday night address, Bush focused not only on new immigration reforms, but also on enforcing existing laws, many of which are aimed at employers, not just laborers.

"Businesses often cannot verify the legal status of their employees, because of the widespread problem of document fraud. Therefore, comprehensive immigration reform must include a better system for verifying documents and work eligibility," he said.

"A tamper-proof card would help us enforce the law and leave employers with no excuse for violating it. And by making it harder for illegal immigrants to find work in our country, we would discourage people from crossing the border illegally in the first place."

On Tuesday, Chertoff said it's also important to disrupt the business aspects of illegal immigration.

"If we look at the business model for the illegal migrant, we have to consider the tremendous economic pressure that is driving people into this country. And it is not an economic pressure that can be addressed simply by dealing with more boots on the ground and more technology at the border itself," Chertoff said.

He said increased efforts through the president's proposed new ID card — which would feature biometric identification and would be harder to falsify — as well as coming down harder on employers who break the law would also help to stem the tide of illegal immigrants.

Aguilar said the increased efforts will disrupt criminal organizations.

"This tactical infrastructure, the engineering, the force multiplication effort is going to help in negatively impacting on those criminal organizations that today are causing deaths of Mexicans, that are causing danger to both — populations on both sides of the river in the U.S. and in Mexico," Aguilar said.

Bush Plan Changes Few Minds About Immigration

Immigration reform could be the administration's single biggest accomplishment this year, but the president's plan so far isn't likely to change many minds on Capitol Hill about how to deal with illegal immigration.

"I applaud President Bush for redoubling his commitments to a comprehensive border security and immigration reform plan. Presidential leadership is necessary to obtain a legislative solution to our immigration problems," said Rep. Jim Kolbe, R-Ariz.

"No, he didn't change my mind," Sen. Saxby Chambliss, R-Ga., told FOX News. He said he intends to vote against the compromise bill if it doesn't change from its current form.

"The president did an excellent job laying out the problem. I particularly appreciated the temporary use of the National Guard," Chambliss said. "What I didn't particularly appreciate were his comments on how someone can just get into this country if they write a check and learn English."

Bush went to great length to support the guest worker plan now being debated in the Senate. The Comprehensive Immigration Reform Act creates a system of penalties for foreign-born residents who entered the country illegally. But it also allows those 11 million to 12 million individuals in the United States to get on a path to citizenship.

But opponents say the guest worker program is nothing more than amnesty.

"I will not support amnesty for illegal immigrants, no matter how many speeches that the President gives in support of that broken idea. Amnesties open routes to legal status for illegal aliens who want to circumvent vital security checks," said Sen. Robert Byrd, D-W.Va, whose statement was also critical of the president's border security funding.

The "real effect" of guest or temporary worker programs "is to legalize the unlawful actions of millions of undocumented workers and the businesses that knowingly employ them," he said.

Aides to conservative lawmakers opposed to the Senate bill told FOX News that the president's speech does nothing to change their bosses' minds, particularly on legalization of illegal immigrants already in the United States. "Amnesty is amnesty," one senior Republican aide said.

A senior Senate Republican leadership aide told FOX News that the emphasis on border security in the last couple of days before the president's speech was a hopeful sign but Bush has a lot more work to do to quell the revolt on this right.

Bush won support from other quarters, including the National Association of Latino Elected and Appointed Officials and Western Growers Association. He earned no kudos from conservative groups and divided backing from border governors.

The task of settling differences between the Senate and House bill could be the biggest barrier to reform. The House bill emphasizes border security and calls for construction of a 700-mile fence along the Mexican border. It also makes no guest worker provision.

"I am not going to get into this 'what if' ... the Senate has to pass a bill," said House Majority Leader John Boehner, R-Ohio. "I don't underestimate the difficulty in the House and Senate coming to an agreement on this issue, but I do think it's possible because I think the American people expect us to do something responsible here."

White House spokesman Tony Snow said that the House and Senate need to find a "middle ground" on the question over granting amnesty, which he said the president opposes, and deporting every illegal immigrant, which the president also opposes.

"What the president's trying to do is, it's a middle course, but it's also a leadership course" by laying down benchmarks that give the House and Senate firm guidance, Snow said.

FOX News' Major Garrett, Molly Hooper, Trish Turner, Sharon Kehnemui Liss and Greg Simmons contributed to this report.

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