As noted in this post, Immanuel Kant seemed the first thinker to self consciously understand they were living in an era of Enlightenment.
Yet George Washington, writing TO THE MARQUIS DE LAFAYETTE, Mount Vernon, 15 August, 1786, did seem to realize they lived in an "enlightened" and "liberal" age:
But let me ask you, my dear Marquis, in such an enlightened, in such a liberal age, how is it possible that the great maritime powers of Europe should submit to pay an annual tribute to the little piratical states of Barbary? Would to Heaven we had a navy able to reform those enemies to mankind, or crush them into non-existence.
Washington too had problems with militant Islamic forces of his day. Yet -- good Enlightenment religionist he -- Washington did not therefore write off Islam entirely. To the contrary, Washington's letter to the Emperor of Morocco, dated March 31, 1791 indicates he thought Islam a true religion that worshipped the same God that Jews and Christians did.