One way of approaching Kant is less through his massive central works and more through his applications of his thought in lesser works.
Here, Kant addresses a "saw" that forms part of received wisdom, and that is that the person who insists on a matter of (scientific or ethical) principle is somehow less than mature.
For example, we are told we must accept the conduct of the war in central Asia, with its high level of secrecy, undocumented civilian casualties and detention without trial of material witnesses as the only possible response to the attack of September 11, and that to apply current international law's theories is the mark of the person out of the loop.
However, to do so ignores a recent development in international law which Kant in another work presaged, and which received attention when traditional international law produced a humanitarian disaster in the Balkans.
Traditional international law, under which the American conduct of the current war operates, is might makes right and asserts as an axiom that the sovereign's will cannot be questioned.
The problem is that this cannot be stated in polite circles in Western democracies today with anything like full theoretical force, since if it is true that the sovereign's will operates without check internationally, this is equally true, when push comes to shove, in the domestic sphere.
If America has the right to bomb civilians and withhold information from journalists internationally, the thoughtful American citizen has no coherent way of objecting to collateral domestic damage to civil liberties. This is shown clearly by the fact that in the post Sep-11 climate, the Administration has been able to pass laws by means of which the government may search an individual's home and only later notify him that the search has been conducted...on the face of it, quite unreasonable in the meaning of our Constitution.
To avoid this painful conclusion, the common response is the one made long ago to Kant, when he made his own ethical and political recommendations based on his central insight: that there are indeed synthetic apriori features of the world that organize thought, and consequently behavior.
This is "that might be right in theory but 'twon't work in practice."
To which Kant replies that the pragmatic objection is actually a theory in and of itself, added as a rider clause to the theory.
Kant's thought has a structural insistence that we think through the consequences of our patches and other repairs to thought. For in the same way that Kant objected to the American Revolution's claim of a "right" of revolution, by quietly pointing out that the right to overthrow the sovereign fails to accomplish the mission, by making the American people (or, in practice, a fascist majority) the real sovereign, anti-theory finds itself in the position of St Augustine' pirate, or the 17th century bucanneer Israel Hands.
This is the usurper who, after usurpation, cannot find a narrative other than that of the sovereign against whom he mounted his rebellion.
The person who'd usurp pedantry and theory in the name of hairy-chested practice finds himself in the same position as Israel hands, who when asked why he turned pirate and slew the gentry, could only claim impure appetite, saying "because I wanted their pickles and wines." That is, the anti-theoretic man of the saw or rule of thumb wants, in real life, to set up shop as the REAL theoretician.
The problem is that his saws are so often incoherent that they require further saws and ultimately result in incoherence. He winds up in charge of a moronic inferno marked by the inability of its elite to provide clear direction, except in the general direction of perdition.
In current international contexts, it is quite convenient to powerful figures to decry theory and denounce the professoriat, for appended to any one of our international committments, it gives the power elite an unlimited blank check. Left romantics only assist this process by hypostatizing the anti-intellectual proletarian style when in fact the current working class is set to intellectual and symbolic tasks.
This is probably the reason for its astonishing vernacular power in so many apparently unrelated areas of American life. For example, as a software developer who's interested in software correctness, I hear this objection frequently to the very idea of any kind of qualitative oversight of software.
There is in general an accepted, and to me quite deviant, disconnect in my culture between our good intentions (or, to be painfully precise, our idea of our intentions as good, and quite unlike those of Islam and the "terrorists") and our results. It is to me constituted in a split between the normative and the description which a close reading of Kant can heal, for Kant seems to be at that rarefied, almost childlike plane before there are words like "theory" as opposed to "practice", and "what I should do" as opposed to what in hell is going on.
Like the forest entered by Alice in Wonderland in which there were no names, Kant manages to identify for us a world, probably the real world, that existed before we dreamt up our cozy categories. We accuse the messenger, Kant, of such dreaming but if you actually trouble to READ his stuff you find a unique purity, which refuses to end discussion with noise about "theory" and "practice"...as if, at the end of the day and in the presence of our common mortality, there was such cozy furniture to begin with.