The manifesto rightly assails Bush for his violations of international law and the American constitution in how he has prosecuted the "Global War on Terror" and the invasion/occupation of Iraq. Good stuff, but it sits uneasily with the signatories support for the Bosnian and Kosovo wars, neither of which fit in nicely with the UN Charter or Article I, Section 8 of the US Constitution.
I also can't endorse the following statement of vulgar Rawlsianism:
When debating policy in the public square, our government should base its laws on grounds that can be accepted by people regardless of their religious beliefs
I doubt this stricture is applied solely to governments. After all, it isn't so much governments that debate policy in the public square, as politicians and citizens, and it would be an inappropriate limitation on democracy to prohibit the latter from bringing their religious commitments to the public sphere. I'm not sure there even are "grounds that can be accepted by people regardless of their religious beliefs," and dispute that it is acceptable to keep people from asserting religious values in the public square. I doubt the signatories have Buddhists for a Free Tibet or Quakers Against the Death Penalty in mind. But what they ask is basically impossible: in Canada, political scientists have long found that religious affiliation is a better predictor of voting behaviour than almost anything else. You might as well have a manifesto denouncing the tendency of the tides to get your feet wet.
Which brings me to the Manifesto's embrace of reason. I'm big on science, and I agree that Bushian Republicans have a bad record in regard to it, but the insistence by American liberals and like-minded progressives in other countries that equality is an empirical fact, rather than a normative guide, is a significant hassle for scientists. Left-of-centre types have also had non-reason-based objections to economic science in my lifetime.
Don't get me wrong. Bush has been a lawless President, and one unusually impervious to empirical disconfirmation, and most of these criticisms hit home. I intend no moral equivalence. As Daniel Larison -- no liberal by any definition -- puts it, "You can vote for the Republic, or you can vote for the Republicans." But even in a short piece, American liberals show some of their own limitations.