The right wing tried to attack John Kerry in 2004 for a lack of patriotism and commitment to American values, just as it is now doing to Obama. It likely fell short of its goal. But the pressure it brought to bear on Kerry, through the Swift Boat ad and other attacks, led people to conclude that Kerry flip-flopped on issues and led them to discount what he said during his campaign.

Similarly, Americans will not buy that Obama is un-American. But the pressure the right brings to bear on him will cause him to appear weak in the face of attacks.

McCain needs to hammer away at the issue of strength and leadership and deal decisively with the problems that crop up in the campaign, while Obama dithers, thinks things through and tries to parse hairs in his responses.

Here the Iraq issue op ens a real opportunity for McCain, where otherwise his support for the war would be a real negative. Iraq is a lot like Social Security. Everyone knows there is a problem, but any solution is immediately shot down. The issue earned the label “the third rail” in our politics, a status that was underscored when Bush’s momentum from his 2004 reelection was smashed against the rocks of Democratic and elderly opposition to his Social Security reform plan.

So it is with Iraq: He who proposes an alternative is doomed. McCain’s position, that we have to stay until we win, is far from popular, but it’s a lot better than unilateral and immediate withdrawal.

And Obama’s opposition to the war begs a host of questions: Shall we retain any presence? What about al Qaeda? What happens if the government falls? Can we let Iran take over? Obama will dither and seem far from decisive as he answers each of these questions. They will make him loo k terrible, just as Kerry — in opposing the war after voting for it — looked like a flip-flopper.

McCain can use the predisposition of voters to see Obama as weak, coupled with the Iraq issue, to make the strength issue his key advantage.