Commentators have been saying that for someone who has been selling a Bold New Approach to politics, Obama has been noticeably short on Bold Policy Proposals:

He’s an inspiring speaker, and given the realities of how presidents exercise power that’s no small thing. But he sure is cautious to a fault. His big foreign policy speech was fine, but cautious and mainstream. His big healthcare speech was fine, but cautious and mainstream. And now his big tax speech is….just cautious and mainstream. I really want to hear something big and controversial from Obama, something that demonstrates a desire to shake up the status quo. But he just doesn’t seem to be willing to take any chances. That’s a shame.

That was Kevin Drum, exactly two weeks ago. And, lo and behold, yesterday Barack Obama stepped to the plate and produced a Bold New Proposal. Rather short on details, as many of Obama’s proposals have been, but a Bold New Proposal nevertheless. As president, he would work to eliminate nuclear weapons from this earth. Not reduce. Eliminate. “Reduce” wouldn’t be bold enough, but “eliminate” fits the bill very nicely, thank you.

Barack Obama, the US Democratic presidential hopeful, pledged on Tuesday that as president he would work towards the elimination of nuclear weapons around the world by reviving the original goals of the nuclear non-proliferation treaty.

In what was his most distinctive foreign policy speech so far, Mr Obama sought to draw a parallel between his campaign and the presidency of John F. Kennedy, who first negotiated the nuclear weapons control that led to the Non-Proliferation Treaty in 1969.

(I’ll pass on the obvious cheap shot. Partly because maybe Jack Kennedy is precisely who he is.)

It was a well produced policy rollout, certainly. Milking the Kennedy theme for all its worth, Obama was “(introduced) by Ted Soren­sen, who was an adviser and speechwriter to Kennedy in the early 1960s”.

Obama made it clear he wasn’t being cautious and mainstream. He was going out on a limb and, exactly as advertised, he was challenging “Washington’s conventional wisdom”. He claimed he was making “practical sense”, not just “political sense”:

Conventional wisdom in Washington has a way of buying into stories that make political sense even if they don’t make practical sense…

He made it clear he wasn’t “declaring US unilateral nuclear disarmament”. We would eliminate our arsenal only if everyone else eliminated theirs.

Now rhetoric is all very well, and undoubtedly Barack Obama’s is better than anyone else on the political firmament these days. But this business of eliminating nuclear weapons is never ever going to fly in practice. And there can be no doubt that Obama is fully aware of that. He’s too smart not to be.

I’m not even going to ask difficult questions like how Obama proposes to convince a country like Iran to abandon its nuclear weapons plans. No, let’s just talk about our friends and allies.

I’m perfectly willing to take Obama’s proposal seriously if and when he’s willing to explain how he’ll get India and Pakistan — with their history of mutual aggression and mutual suspicion — to give up their nuclear weapons. Or Israel.

I’m perfectly willing to take him seriously if he can outline any kind of approach that sounds like it may actually have some hope of working.

Otherwise, this is all just carefully calculated electioneering. Making promises you know perfectly well you can never keep, making them because you know people will swallow them today, and why worry about tomorrow, when the worst case scenario is that you’re president and somebody heckles you about not keeping your campaign promises?

Isn’t that the oldest trick in the book? Is this the kind of stuff Obama meant when he promised “a fundamental break from the way we’ve been doing business”? Or did he mean lofty things but now finds himself reduced to cynically making promises that cannot be kept, making them because he finds he has to, and because he knows he can make them sound really good today?

Don’t get me wrong. I’m all for reducing the world’s nuclear arsenal. As far as I’m concerned, anyone who succeeds in reducing it even by 50% deserves the Nobel peace prize, no questions asked.

“Ivo Daalder, a senior foreign policy adviser to Mr Obama,” says: “The conventional thinking on nuclear weapons in Washington is that we need to keep nuclear weapons for all sorts of contingencies … In this speech he is challenging that entire basis of thinking.”

If that’s all Obama had said, if he’d dedicated himself to substantially reducing the world’s nuclear arsenal, I’d be standing up and applauding right now. But that isn’t what he said. Because, for better or for worse, the perception was that politically he needed to be saying more. It wasn’t enough to make practical sense. What he needed was a political home run. So he reached for it. I’m not sure he hit it out of the park either. Too many people seem to regard that goal of eliminating nuclear weapons as unattainable. And they are now looking very suspiciously at Obama. Because he seems to be betraying the very political persona he has been at such pains to construct for himself. And given the campaign Obama has run, once you start seeing him as hypocritical, what else is left? Once you start seeing him as willing to say whatever it takes to get elected, what’s the difference between him and Hillary Clinton except for the killer oratory?