Mitt Romney, teeing up his overseas trip, accused President Obama on Tuesday of threatening America's position as "leader of the free world" -- using a speech to the Veterans of Foreign Wars to hammer the president over scheduled defense cuts, foreign policy and recent high-profile security leaks.
"Sadly, this president has diminished American leadership, and we are reaping the consequences," Romney said.
The Republican presidential candidate spoke to the VFW convention in Reno, Nev., one day after Obama addressed the same gathering. Romney spoke ahead of an overseas tour that will take him to Britain, Israel and Poland.
In his speech, Romney suggested that Obama has shunned America's friends while being too lenient with its foes. He said the country's economic woes are further endangering its position of strength in the world.
But he also accused the president of failing to keep a tight ship when it comes to sensitive security information -- claiming the administration leaked such details for "political advantage" and calling for a "full and prompt" independent investigation.
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Romney seized on a comment Monday from Sen. Dianne Feinstein, D-Calif., chairwoman of the Senate Intelligence Committee: "I think the White House has to understand that some of this is coming from their ranks," the senator told a World Affairs Council forum.
The California lawmaker said she was certain that Obama, who receives a daily intelligence briefing, isn't disclosing secret information, but she was uncertain about others at the White House.
Attorney General Eric Holder has appointed two attorneys to lead the investigation into who leaked information about U.S. involvement in cyberattacks on Iran and about an Al Qaeda plot to place an explosive device aboard a U.S.-bound airliner.
Romney, in his remarks Tuesday, called the leaks a "national security crisis."
"This conduct is contemptible. It betrays our national interest. It compromises our men and women in the field. And it demands a full and prompt investigation by a special counsel, with explanation and consequence," Romney said. "Whoever provided classified information to the media, seeking political advantage for the administration, must be exposed, dismissed, and punished. The time for stonewalling is over."
Romney, who also complained about the details that flowed out of Washington following the raid that killed Usama bin Laden, said the administration cannot wait until after Election Day to investigate.
"Exactly who in the White House betrayed these secrets? Did a superior authorize it? These are things that Americans are entitled to know," Romney said. "And let me be very clear: These events make the decision we face in November all the more important. What kind of White House would reveal classified material for political gain? I'll tell you right now: Mine will not."
The administration has pushed back on the idea that anyone in the White House was involved in the leaks.
Obama campaign spokesman Ben LaBolt also slammed Romney's speech Tuesday.
"With all of the complex global challenges facing our nation today, Governor Romney's much-hyped foreign policy speech once again is all bluster, offering no specific plans for our relations with any region of the world. He's about to embark on a foreign trip where his aides have promised no policy, just photo-ops and fundraising. By resorting to cheap attacks that lack credibility rather than answering the most basic questions about his foreign policy agenda, Governor Romney has simply not passed the commander-in-chief test," he said.
Obama stressed his commitment to America's security during his address to the VFW on Monday. The president reminded the audience that he made good on his promise to find and kill Usama bin Laden, and he vowed more job-finding and professional help for returning veterans.
Obama also claimed Republicans are working against the military's interest by pushing for tax cut extensions for top earners -- suggesting that will exacerbate the deficit, in turn allowing automatic spending cuts for the Pentagon to kick in.
"Instead of making tough choices to reduce the deficit, they'd rather protect tax cuts for some of the wealthiest Americans, even if it risks big cuts in our military. And I've got to tell you, VFW, I disagree," Obama said.
But Romney said that if elected president he will not allow the defense cuts to take place.
"Today, we are just months away from an arbitrary, across-the-board budget reduction that would saddle the military with a trillion dollars in cuts, severely shrink our force structure and impair our ability to meet and deter threats," he said. "Those cuts would only weaken an already stretched VA system and our solemn commitment that every veteran receives care second to none. If I am president of the United States, I will not let that happen."
Romney also took an implicit swipe at Obama's posture overseas, describing himself as an "unapologetic believer in the greatness of this country."
"I am not ashamed of American power," Romney said. "I take pride that throughout history our power has brought justice where there was tyranny, peace where there was conflict, and hope where there was affliction and despair. ... This century must be an American Century."
The Associated Press contributed to this report.