I think that the best answer is the geographic location: many other countries (Sweden for example) have tried being neutral at different times but did not manage to: but the fact that the US has only two boundaries, and that both other countries also have a history of fighting from independence from a European power, makes it possible that unless US decideds to get involved in international politics, it can be "left alone".
It was set at the Mississippi river, hope this helps
It shows his fascination with European art. The Portuguese Jesuits knew this so they brought him a piece of European art which he welcomed because of his love for it. He was known for taking many things from European art and incorporating them into the culture of his people and their art.
The United States wanted a method of export and transportation to and from the United States originally when Panama was a part of Colombia. This is why they helped Panama's revolution to become its own independent country. If they had good relations and Panama went as planned, the US could finally build the canal they wanted so badly. The canal now allows transportation of many of the goods we purchase and use today here in the United States.