Republican senators hammered former GOP Sen. Chuck Hagel at his confirmation hearing Thursday on issues ranging from Israel and Iran to his support for a group that advocates the elimination of nuclear weapons. But with most Democrats in his corner, an unflustered Hagel seems headed for approval as defense secretary.Hagel, a former two-term senator from Nebraska, described his views as mainstream and closely aligned with those of President Barack Obama, the Democrat who nominated him. But several GOP members of the Armed Services Committee sought to portray him as radical and unsteady. Sen. Deb Fischer, R-Neb., called his ideas "extreme" and "far to the left" of Obama.Hagel said he believes America "must engage not retreat in the world," and insisted that his record is consistent on that point.He pointed to Iran and its nuclear ambitions as an example of an urgent national security threat that should be addressed first by attempting to establish dialogue with Iranian rulers, although he said he would not rule out using military force."I think we're always on higher ground in every way international law, domestic law, people of the world, people of the region to be with us on this if we have ... gone through every possibility to resolve this in a responsible, peaceful way, rather than going to war," he said.He pushed back on the notion first raised by one of his harshest Republican critics, Sen. James Inhofe of Oklahoma that he favors a policy of appeasement."I think engagement is clearly in our interest," Hagel told Sen. Saxby Chambliss, R-Ga., who denounced the idea of negotiating with a "terrorist state.""That's not negotiation," Hagel said. "Engagement is not appeasement. Engagement is not surrender."His fiercest exchange came with Sen. John McCain, R-Ariz., a fellow Vietnam veteran, onetime close friend and a vote that could carry considerable sway. Politics and Hagel's evolving opposition to the Iraq war caused a split between the two men that was on full display.McCain suggested that Hagel and his critics were not quibbling over small matters."They are not reasonable people disagreeing; they are fundamental disagreements. Our concerns pertain to the quality of your professional judgment and your world-view on critical areas of national security," he said.McCain pressed Hagel on whether he was right or wrong about his opposition to President George W. Bush's decision to send an extra 30,000 troops to Iraq in 2007 at a point when the war seemed in danger of being lost. Hagel, who voted to authorize military force in Iraq, later opposed the conflict, comparing it to Vietnam and arguing that it shifted the focus from Afghanistan."Were you right? Were you correct in your assessment?" McCain asked."I would defer to the judgment of history to sort that out," Hagel said as the two men talked over each other."The committee deserves your judgment as to whether you were right or wrong about the surge," McCain insisted.Unable to elicit a simple response, McCain said the record should show that Hagel refused to answer. And he made it clear that he would have the final word with his vote, which he said would be influenced by Hagel's refusal to answer yes or no."I think history has already made a judgment about the surge, Sir, and you're on the wrong side of it," he said.Responding to criticism from outside GOP-leaning groups, Hagel repeated his regrets about using the term "Jewish lobby" to refer to pro-Israel groups. He said he should have used another term and should not have said those groups have intimidated members of the Senate into favoring actions contrary to U.S. interests."I'm sorry and I regret it," Hagel said. "On the use of 'intimidation,' I should have used 'influence,' I think would have been more appropriate."At one point, Hagel mistakenly said the Obama policy toward Iran is "containment" even though the former senator has said all options, including military force, should be on the table. He was handed a note and corrected himself.Hagel was the lone witness in a jam-packed hearing room at a session that could be crucial in determining whether he will win Senate confirmation and join Obama's second-term national security team. He spoke out forcefully for a strong military while trying to explain 12 years of Senate votes and numerous statements."No one individual vote, no one individual quote or no one individual statement defines me, my beliefs, or my record," Hagel said in his opening statement. "My overall worldview has never changed: that America has and must maintain the strongest military in the world, that we must lead the international community to confront threats and challenges together, and that we must use all tools of American power to protect our citizens and our interests."Hagel, 66, would be the lone Republican in Obama's Cabinet, the first Vietnam veteran to be defense secretary and the first enlisted man to take the post. That last point was highlighted by committee Chairman Carl Levin, D-Mich."It would be a positive message for our soldiers, sailors, airmen and Marines in harm's way around the world to know that one of their own holds the highest office in the Department of Defense and that he has their backs," Levin said.Two former committee chairmen Democrat Sam Nunn and Republican John Warner introduced the nominee."War for Chuck Hagel is not an abstraction," Nunn said.Hagel has the announced backing of about a dozen Democrats and the tacit support of dozens more who are unlikely to embarrass the president by defeating his Cabinet pick. One Republican Sen. Thad Cochran of Mississippi has said he will vote for his former colleague.Eight Republicans, including four members of the Armed Services panel, have said they will oppose Hagel's nomination. Dan Coats of Indiana, who served with Hagel in the Senate, and Marco Rubio of Florida announced their opposition on Thursday.Democrats hold a 55-45 advantage in the Senate and a 14-12 edge on the committee.Republicans repeatedly questioned Hagel about a May 2012 study that he co-authored by the advocacy group Global Zero that called for an 80 percent reduction of U.S. nuclear weapons and the eventual elimination of all the world's nuclear arms.The group argued that with the Cold War over, the United States can reduce its total nuclear arsenal to 900 without sacrificing security. Currently, the U.S. and Russia have about 5,000 each, either deployed or in reserve. Both countries are on track to reduce their deployed strategic warheads to 1,550 by 2018, the number set in the New START treaty that the Senate ratified in December 2010.Fischer, the Nebraska Republican, quoted from the Global Zero report and expressed strong misgivings."Many of my colleagues are concerned you've changed your views. My concerns are that you haven't changed your views. You continue to hold extreme views, far to the left even of this administration," said Fischer.In last year's Senate race, Hagel endorsed Fischer's Democratic rival, former Sen. Bob Kerrey, who also is a Vietnam combat veteran.Hagel insisted that the report was merely illustrative and said it wasn't realistic to consider unilateral nuclear weapons reductions.