Former Republican Sen. Chuck Hagel was put on the spot Thursday by Republican members of the Senate panel considering his nomination to be defense secretary.
He's been challenged over his past statements on Israel, Iran, Iraq and nuclear weapons.
Sen. John McCain, a supporter of the troop "surge" in Iraq in 2007, tried to get Hagel to admit he was wrong in opposing that influx of 30,000 U.S. troops. Hagel -- who has said the Iraq war shifted the focus from Afghanistan -- said he would "defer to the judgment of history" to sort that out.
Republicans repeatedly questioned Hagel about a study that he co-authored last year that called for an 80 percent cut in U.S. nuclear weapons, and elimination of all nuclear-armed intercontinental ballistic missiles.
Hagel said the report was illustrative, and that it wasn't realistic to consider unilateral reductions.
And Sen. Lindsey Graham was harshly critical of Hagel for failing to sign letters in past years on designating Hezbollah a terrorist organization and backing Israel.
Pushing back against the criticism, Hagel said there's no one vote or statement that defines him or his beliefs.
Hagel appears to be on a path to confirmation despite the Republican opposition.