- Most of the issues that propelled conservatives to power have been addressed.
I'm not sure I totally agree with this, and even Brooks goes on to say that some of the key issues that brought conservatives to power have been left at a stand-still—shrinking the government, for example. I think a bigger problem is that conservatives rode in on a bunch of issues that people assumed were simple, but are in fact much more complex. Conservatives used their strong stances on things like war and crime, religion in the public sphere, and fiscal policy to gain power, but we're realizing now that those strong stances have mixed consequences.
- Conservatism has been semi-absorbed into the Republican Party.
I think Brooks is being a little coy here. What he means to say is, a lot of "good men" sold out. And it's definitely true, as it is any time a group gains a lot of power quickly.
- Conservative media success means intellectual flabbiness.
Brooks means that when cons could only listen to media they assumed was liberal-ridden, they could exercise their mental powers trying to portray everything they read as liberal propaganda. Well, actually, that may be a little bit harsh, but it is a fact that paranoia, in gifted individuals, does exercise the mind.
- Conservatives have lost their governing philosophy.
That governing philosophy, for Brooks, was smaller government. But that hasn't just been lost; it's been resoundingly rejected by both Bush and by the evangelical wing—the objective now is not less government, but a broader conception of what gets (explicitly) governed.
- Conservative Republicans have lost touch with their base.
Translation: the conservative policies as they've been enacted screw those who vote for them. I think Brooks would say that wasn't the intent of the men who founded modern conservatism, but that's kind of like saying socialism's intentions were always good. If an idea fails big-time, there are probably big problems with it.
- Conservatives have not effectively addressed the second-generation issues.
Essentially, the world has changed in ways that have made conservatism's essential propositions inoperable for the most part—the problems we're dealing with now can't be solved by the insights William F. Buckley and Leo Strauss came up with 50 years ago and more. I wouldn't say liberals have a vastly superior understanding of the vastly changed world, but some things on the liberal side—like pluralism—are significantly better than their correspondent conservative philosophical notions.
The major difference, I believe, is that liberals have a better grip on the idea that the world is significantly different from the one that the US dominated post-WWII. We just haven't figured out what those differences exactly are. But give me some time—at least until the end of grad school—and I'll have it pretty well nailed down.