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Sen. John Kerry (search) slammed President Bush (search) Thursday for taking the United States into war in Iraq without enough global support, while the commander in chief said he doesn't need a permission slip from the rest of the world to protect America and its interests.

In the first of three presidential debates that could greatly influence the outcome of what's expected to be a nail-biter election on Nov. 2, Bush also said the world was safer with Saddam Hussein gone and Kerry said the real focus should have been on Afghanistan.

The first question, which went to Kerry, was: "Do you believe you can do a better job than President Bush in preventing another 9-11 type terror attack on the United States?"

"I can make America safer than President Bush has made us, and I believe President Bush and I both love our country equally but we just have a different set of convictions on how to make America safer," Kerry said.

Bush said, "The best way to protect this country is to stay on the offense ... we have to be right 100 percent of the time; the enemy only has to be right once.

"I wake up every day thinking about how best to protect America — that's my job," the president continued. "But you'd better have a president who chases these terrorists down and brings them to justice before they hit us again."

Both candidates said nuclear proliferation was their No. 1 concern for the country right now — with Bush specifying that weapons of mass destruction in the hands of terrorists was his utmost worry.

The president and his Democratic challenger squared off at the University of Miami in Coral Gables, Fla., and spent 90 minutes focusing on foreign policy and homeland security — two topics that currently are working in the incumbent's favor, according to recent polls. The face-off was moderated by Jim Lehrer of PBS. Contrary to one of the rules of the debate, some networks, including FOX News, offered a split screen to viewers so they could see both candidates' reactions at the same time.

With less than four weeks until the election, the polls show Bush with a small lead and several close battleground states. Many political insiders agreed that this debate — likely to be the most watched of the three — was Kerry's big chance to get the momentum swinging back in his favor.

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Saying Bush's leadership in Iraq has left the United States' alliances "in shatters," Kerry said his plan for uniting more countries in the effort in Iraq is to strengthen the Iraqi military faster, convening a summit of all allies on Iraq, going after terror financing "more authoritatively," reaching out to the Muslim world "which the president almost has not done," and isolating radical Islamic Muslims and "not have them isolate the United States of America."

"I will hunt down the terrorists wherever they are, but we also have to be smart," Kerry said, adding that he, if elected, will lead a country that won't divert its attention from the hunt for Usama bin Laden in Afghanistan to Iraq.

Bush responded with familiar battle cries, saying, "Sept. 11 changed how America must look at the world, and since that day our nation has been on a multi-pronged strategy to keep our country safer."

That includes pursuing Al Qaeda (search) — Bush noted that 75 percent of the terror ring's leadership has been either killed or captured — and "the rest of them know we're after them," the president added.

He also noted that his administration has upheld the doctrine that those countries that harbor terrorists are just as guilty as the terrorists themselves, and that America's acts have helped 10 million people in Afghanistan registered to vote for elections there. Getting rid of the threat in Iraq, Bush stressed, was a vital part of that multi-pronged strategy.

"In Iraq we saw a threat, and we realized after Sept. 11 we must take threats seriously before they materialize," the president said. "Saddam Hussein (search) now sits in a prison cell and America and the world are safer for it."

Bush was also asked if he thought the election of Kerry would increase the chance of another Sept. 11-type attack on this country.

"I believe I'm going to win because the American people know I can lead," Bush responded. "I understand everyone in this country doesn't agree with the decisions I've made — and I've made some tough decisions — but people know where I stand."

Iraq War: A 'Colossal Misjudgment?'

Kerry said Bush has made "colossal misjudgments" when it came to Iraq, including not getting the support of the United Nations behind the war effort there at a time when Afghanistan should have been the focus.

"Does that mean ... Saddam Hussein was more important than Usama bin Laden? I don't think so," Kerry said.

Bush countered that, saying bin Laden has been "isolated" and, "I didn't need anybody to tell me to go the United Nations. I decided to go there myself … I hoped the free world would understand we should force Saddam to listen up."

Bush also took several jabs at Kerry for his so-called flip-flops on the Iraq war.

"What my opponent wants you to forget is he voted to authorize the use of force. Now he says it's the wrong war in the wrong place," Bush said. "What message does that send our troops? What message does that send our allies? What message does that send the Iraqis? The way to win this is to be steadfast and resolved and to follow the plan that I've outlined."

The president also made reference to a comment Kerry made that has dogged his campaign of late: that he voted for the $87 billion authorization for the war before he voted against it.

Kerry had a ready response.

"I made a mistake in how I talked about the war. The president made a mistake in invading Iraq," Kerry said. "Which is worse?"

When the Troops Come Home

Kerry has said that if elected, he would pull American troops out of Iraq within six months, although later he said he would not impose such a fast deadline. Bush said that would only signal weakness to terrorists in the region, and that once Iraq is on its feet and ready to take the reins of its own security forces and democratic process, that's when U.S. servicemen and women can begin coming home.

"We'll never succeed in Iraq if the Iraqi citizens don't take the steps to protect themselves," Bush said. "That's when, and I hope it's as soon as possible, but I know putting artificial deadlines won't work … you can't do that and expect to win the War on Terror."

The Democratic challenger criticized the Bush administration for not having a solid game plan for how to exit the Iraqi theater.

"Iraq was not even close to the center of the War on Terror before the president invaded it," Kerry said. "You don't take America to war unless you have a plan to win the peace … this president, I don't know if he sees what's really happening out there but it's getting worse by the day."

The United States needs a more global effort in Iraq, Kerry stressed, but Bush noted that 30 countries are contributing in some way or another. Poland has contributed troops, he noted, and Jordan is helping train the Iraqi police while organizations like NATO are also assisting in the effort.

"I don't appreciate a candidate for president denigrating the contributions" by America's allies, Bush said, adding that Kerry has called the coalition's partners in the effort "the coerced and the bribed."

Lehrer asked the commander in chief whether the American lives lost were worth the effort in Iraq.

"I think it's worth it because I know in the long term, a free Iraq, a free Afghanistan will set such a powerful example in a part of the world that's so desperate for freedom," Bush replied after saying the hardest part of his job is knowing Americans are dying for the cause and that he always grieves with families who have lost loved ones. "It will change the world so we can look back and say we did our duty."

Kerry, a Vietnam War veteran who, throughout the debate, made mention of his experiences as yet another reason he's qualified to lead the nation, brought back sentiments from that era and the lessons learned.

"The question, is it worth the costs, reminds me of my own thinking when I came back from that war," Kerry said. "It's vital for us not to confuse the war, ever, with the warriors. That happened before, that's one of the reasons I think I can get the job done ... that's the most noble thing anyone can do and I want to make sure the outcome honors that nobility."

Nukes, Darfur and Character Issues

Kerry said the president should have the authority to launch preemptive strikes if he sees a threat to national security, "but if and when you do it, you've got to do it in a way that passes the test, passes the global test where your countrymen, your people, understand fully why you're doing what you're doing and you can prove it with legitimate reasons."

Bush took issue with that, saying the United States shouldn't have to pass any "global test" and get approval to protect itself.

"You take preemptive action to protect the American people, and you act to make this nation more secure," the president added.

On the issue of North Korea and the nuclear threat there, where Kerry is pushing for bilateral talks between the Asian nation and the United States, Bush said that would be a mistake and that six-way talks that currently include countries such as China would fall to the wayside.

Kerry voiced concerns about conditions in Russia, saying that government solidification and crackdowns taking place under President Vladimir Putin go beyond what's necessary to combat terror.

Bush said he has a good personal relationship with Putin and that he's a great ally in the War on Terror, but that he disagrees with some things the Russian leader is doing.

U.S. representatives and others have officially declared that genocide is taking place in the Darfur region of Sudan. So far, the United States has not committed troops to the region but has sent $200 million in aid, with more to come.

Kerry said more can be done to press the African Union to resolve the humanitarian crisis there and that the United States must provide more logistical support. But sending U.S. troops is near impossible, he said, because they're now overextended.

"We've got guards and reserves who are doing double duties — we've got a back-door draft in the United States today," Kerry said, adding that if elected, he would add two active duty divisions to the Army to position across the globe, but not Iraq, and would double the number of special forces to hunt down terrorists.

One of the most pointed questions of the debate first went to Bush, who was asked what character issues he thought were serious enough to deny Kerry the job at 1600 Pennsylvania Avenue.

"Whew — that's a loaded question," Bush said.

He heralded Kerry's service to the country as well as his 20 years in the Senate, "but I'm not so sure I admire his record. I won't hold it against him that he went to Yale — nothing wrong with that," the president added, showing a bit of his humorous side.

"My concerns about the senator ... is that he changes his positions, he changes his positions on the war in Iraq … you cannot lead if you send mixed messages, mixed messages send the wrong message to our allies," Bush said. "We change tactics when we need to but we don't change our beliefs."

Kerry tackled the "issue of certainty" that has dogged him throughout the campaign and turned the tables on the president.

"It's one thing to be certain, but you can be certain and be wrong. It's another to be certain and right and be certain and moving in the right direction … or learn new facts and put them to use and change to get your policy right … and certainty sometimes can get you into trouble."

Who Can Lead Us to the 'Valley of Peace?'

In closing out the night's stand-off, Kerry reminded those listening that he's served this country in war time and he'll go to bat for his country whenever it's needed. The comments come despite attacks of late from the Swift Boat Veterans for Truth and others, who have challenged Kerry's stories of heroism there and the number of medals he received.

"I know that for many of you sitting at home, parents of kids in Iraq, you want to know who is the person who can be your commander in chief and get your kids home and get the job done and win the peace," Kerry said in closing. "Let me look you in the eye and say to you: I defended this country as a young man in war and I will defend it as president of the United States.

"I believe America's best days are ahead of us because I believe the future belongs to freedom, not to fear. That's the country I'm going to fight for."

Bush repeated a theme he stressed throughout the debate — that Kerry's changing stances on some issues will only hurt the nation.

"If America shows uncertainty or weakness in this decade, the world will drift toward tragedy. That's not going to happen so long as I'm president," Bush said, adding that in the next four years he will strengthen homeland defense, reform the nation's intelligence and defense apparatus and go after terrorists abroad before they reach America's shores.

"We've done a lot of hard work together over the past three-and-a-half years, we've been challenged … we've climbed the mighty mountain and I see the valley below and it's a valley of peace."

Vice President Dick Cheney (search) and North Carolina Sen. John Edwards (search) — Kerry's vice presidential hopeful — will square off on Tuesday, Oct. 5.