David Brooks:

And yet as any true conservative can tell you, the sort of rational planning Mitt Romney embodies never works. The world is too complicated and human reason too limited. The PowerPoint mentality always fails to anticipate something. It always yields unintended consequences.

And what Romney failed to anticipate is this: In turning himself into an old-fashioned, orthodox Republican, he has made himself unelectable in the fall. When you look inside his numbers, you see tremendous weaknesses.

For example, Romney is astoundingly unpopular among young voters. Last month, the Harris Poll asked Republicans under 30 whom they supported. Romney came in fifth, behind Rudy Giuliani, Mike Huckabee, John McCain and Ron Paul. Romney had 7 percent support, a virtual tie with Tancredo. He does only a bit better among those aged 30 to 42.

Romney is also quite unpopular among middle- and lower-middle class voters. In poll after poll, he leads among Republicans making more than $75,000 a year. He does poorly among those who make less.

If Romney is the general election candidate, he will face hostility from independent voters, who value authenticity. He will face hostility from Hispanic voters, who detest his new immigration positions. He will face great hostility in the media. Even conservative editorialists at places like The Union Leader in New Hampshire and The Boston Herald find his flip-flopping offensive.