The office of president is one of the most prestigious in the world, but those holding this office tend not to be the best people in the world. Indeed, one could go so far as to say some of them have enacted full blown atrocities. Although the number of presidents that have committed atrocities is numerous, there are about five or six that really stand out, and when viewed in a historical context one is often surprised that these things were allowed to happen in the first place.
John Adams is one president that a lot of people respect. After all, this is a man that helped author the declaration of independence! But when America was caught in a war with France, John Adams ended up going against the very constitution he himself had written. He passed an act that made it illegal for a citizen of America to speak against the government, and he also made it legal for someone with connections to France to be deported without a reason. This is obviously highly unconstitutional, but this did not John Adams from implementing it. The constitution was not sacred from the very first generation of politicians.
Another president that committed a violation of ethics will surprise you. His name is Abraham Lincoln. Lincoln is without a doubt the most famous president in US history, except perhaps for George Washington, and what he did to end slavery is truly admirable. However, a member of the executive branch of government, even the heads of that branch the President themselves cannot try to interfere with the workings of another branch. The judiciary is meant to be independent so that it can work without the president gaining absolute power. This did not stop Lincoln from trying to arrest Chief Justice Roger Taney, though, after he had a disagreement with him. Similarly to John Adams, Lincoln tried to suspend habeas corpus which would have prevented him from arresting someone without a reason so that he could attempt to arrest Taney.
Teddy Roosevelt is famous for a lot of things, but perhaps his most pertinent claim to fame is the fact that he had the Panama canal built. The manner in which he had it built, though, was rather interesting because it was such an enormous abuse of his powers. He used his diplomatic power to prevent Panama from seceding from Colombia when Panama asked for more money for building the canal. This had long term implications for the area, and America ended up reaping all of the benefits. Panama ended up becoming independent, but an American puppet was placed as the head of state.
American Presidents have a lot of power, and in spite of all of the checks and balances there were a lot of times when the power ended up going unchecked. Only time will tell how the American political machine would end up shaping over the years, even though it has remained relatively stable so far.