It seems to me Kant's CI supports libertarianism. — moralpanic
It may be worth considering that Kant did not argue that reason is self sufficient regarding the source of the energy needed to bring about good outcomes in the relationships between rational individuals. In his
Critique of Judgement, he says:
"Every rational being would have to continue to recognize himself as firmly bound by the precept of morals, for their laws are formal and command unconditionally , paying no regard to ends (as the subject-matter of volition). But the one requirement of the final end, as prescribed by practical reason to the beings of the world, is an irresistible end planted in them by their nature as finite beings. Reason refuses to countenance this end except as subject to the moral
as inviolable condition, and would only have it made universal in accordance with this condition. Thus it makes the furtherance of happiness in agreement with morality the final end. To promote this end - so far, in respect of happiness, as lies in our power- is commanded us by the moral law, whatever the outcome of his endeavour may be. The fulfillment of duty consists in the form of the earnest will, not in the intervening causes that contribute to success."
451
Kant goes on to say that the earnest will involves belief in God. To emphasize the need for enthusiasm in this regard. he misrepresents Spinoza a few paragraphs later:
"Let us then, as we may, take the case of the righteous man, such, say, as Spinoza, who considers himself firmly persuaded that there is no God and - since in respect of the Object of morality a similar result ensues -no future life either. How will he estimate his individual intrinsic finality that is derived from the moral law which he reveres in practice? He does not require that its pursuit should bring him any personal benefit in this or any other world. On the contrary, his will is disinterestedly to establish only that good to which the holy law directs all his energies. But he is circumscribed in his endeavor. He may, it is true, expect to find a chance concurrence now and again, but he can never expect to find in nature a uniform agreement - a consistent agreement according to fixed rules, answering to what his maxims are and must be subjectively, with that end which yet he feels obliged and urged to realize."
452 (both passages are from the translation made by James Creed Meredith)
To hear Spinoza's side of this topic, one can read chapter 14 of
A Theologico-Political Treatise.
Getting back to the nature of the "rational" individual, Kant depicts the element of personal interest as critical to what makes values "cosmopolitan."