In the early 19th century, Italy was split into several small kingdoms, princedoms and city-states, and this had been the political reality of Italy since the Middle Ages.
Some of these smaller Italian states were under the control of foreign powers, like Piedmont, which was controlled by Savoy. However, most of them were more or less independent.
Political opponents of President John Adams opposed the Alien Enemies Act of 1798 because it stripped American citizens of the right to free speech, which blatantly violated the Constitution.
The U.S. military is subordinate to the Federal (civilian) government. Note that the US Congress controls the budget, and that the President is required to ask for a declaration of war, and the Congress then votes to approve or disapprove the request.
