David Frum worries about a Ron Paul convention speech:

But it’s hard to imagine Ron Paul giving Mitt Romney the endorsement that Huckabee and Romney gave McCain—and even if he did, it’s dangerously easy to imagine that such support would, like Buchanan’s in 1992, do the ultimate ticket more harm than good.

I’m not sure how one would measure this. I have seen a few references recently to Buchanan’s 1992 convention speech in connection with a possible speech by Paul this year, and the assumption is that Buchanan’s remarks somehow undermined or harmed Bush’s prospects in the general election. I suppose one could argue that the primary challenge itself had exposed Bush’s weakness within the party, which was not going to be fixed by an endorsement from the primary challenger, but that’s not the claim being made here. The argument is that Buchanan’s speech, which was focused above all on rallying his supporters behind Bush, actually made things worse for Bush than they would have been otherwise. The alternative to having him speak at the convention would have been to ignore and dismiss Buchanan and his supporters, which certainly would not have boosted turnout for Bush or prevented defections to Perot.

If anything, I think it is more likely that Buchanan’s endorsement shored up Bush’s support with Republican and independent voters that would have otherwise gone to Perot, some of whose general election themes matched those of Buchanan. Obviously, culture war issues were important ones for Buchanan, but they were also the issues on which Buchanan could find some common ground with Bush against Clinton. It wasn’t as if he could credibly give a ringing endorsement of NAFTA or the Gulf War or Bush’s “new world order” rhetoric. He didn’t support any of those things, and everyone knew it. It’s hard to escape the conclusion that some pundits remember Buchanan’s 1992 speech as “disastrous” because they didn’t (and still don’t) share the views expressed in it and not because of any demonstrable effect that it had on Bush’s support.

Mr. Buchanan argued later on that Bush’s numbers improved in the wake of the speech and the convention:

Listening with the Illinois delegation, Ted Koppel said: “They walked out of here tonight enthusiastic, they walked out of here with something that Republicans have not had for quite a few months, a sense of optimism . . . our ABC poll, taken over the past five days, shows the gap narrowing to 20 points … By tomorrow, that gap will have appreciably narrowed. You can count on it.”

Mr. Koppel was right.

The overnight Hotline poll showed Mr. Bush soaring from 16 points down Monday, to 6 points down Tuesday, a 10-point leap in 24 hours, best day of the ’92 campaign. Other polls showed similar surges.

The New York times-CBS survey that had Mr. Clinton leading Mr. Bush by 18 points just days before Houston found Mr. Clinton two points ahead, 48 to 46, the night the president spoke.

We had shifted the agenda from the economy, where 80 percent of the country thought America was “on the wrong track,” to issues of morality and culture, Mr. Clinton’s weakest suits.

I suppose it is possible that Bush would have done no worse in that election had he not received Buchanan’s endorsement, but it is extremely far-fetched to believe that he would have done any better.