If there is one central problem that suffuses critical theory, it is the relationship between reason and action, or reason and practice. Consider:
For a long time, philosophers have assumed that just getting your concepts straight is enough to determine action. If we can figure out what the "good" is, for instance, it should lead us to proper action. Socrates thought that no one knowingly does evil. You always do what you believe is good. So the problem is with belief, not with action.
In the Enlightenment, this belief about reason comes to a head. We can know everything, in principle, and this leads to understanding the right, and also motivates correct action.
Except that it was clear that this wasn't true. Highly intelligent people did very bad things. Highly developed societies just found better ways to wage war. And, more significantly than that, our reason, which was supposed to be morally neutral (remember, moral decisions are about action, which comes after reason) in fact seems to have morality built in. Where could it have come from?
We can put this in political terms as well. How is it possible to have political action and reflective thought at the same time?
And, there's a scientific angle as well. How do we put together freedom with science's attempts to find causal mechanisms in everything?
The current Republican regime is a good example of the problems that critical theory is concerned about. The Bush government was elected on the premise of moral order, a strong set of values. What are these values? They are mostly abstract (embodied in propositions), mostly negative (note the interpretation of values in terms of "no gay marriage", "no stem cell research", etc. in the recent election), and antithetical to thought. These values are held not because they have been arrived at through reason, but because they are part of a traditional moral code that itself has no reasonable defense. The rules are held because they are given in a text, not because they have been debated by society. And indeed, morality is largely seen that way.
What's the problem with this? Well, we don't have the Enlightenment problem of believing that reason can work out value first, and then we just apply that. We have something before that. We have ideology, in the true sense, in that there is a form of life built on a set of ideas. We can also see the role of domination here, in another sense of ideology: any doctrine or belief that supports or justifies the economic and political domination of one class over another. (see Marx's The German Ideology on this) There is clearly ideology involved - diversity is not a value, but homogeneity is, and that on the terms of a specific group of people. Difference is rendered as sin.
Critical theory seems to have a useful function in the current political situation. However, it has to deal with the problem of the reality based community. If it is really true that reason is rendered relative, and that action establishes reason, how might critical theory respond?
The problem is deeper than it seems. One could try to draw on Hegel and his dialectical reasoning, and suppose that reason is a historical process. The problem with this is that Hegel's version of reason subsumes difference under one umbrella. At its worst, it can be totalitarian. We can end up thinking that everything will ultimately come under one account of things. This is why Adorno argued for negative dialectics, which did not subsume everything under the progress of reason, but rather preserved difference.
In conditions of political or social domination, reason can become the child of action, in the sense that one can rationalize existing conditions as being right or good. Or, action can be the child of reason, in the sense that concepts are worked out abstractly and then acted up, as if they were a script. Neither relationship really integrates reason and action. The result, many times, is that one is ignored in favour of the other. The "reality based community" passage is a good case in point - reason is ignored, left for Democratic analysts, while the regime acts in the world.