yes, America could still in fact get a large territory. They could get it by force (war), Buy the land, or a treaty. The bigger question however, is it worth doing it. If America wants to get the land by war that just adds to what the're doing in the middle east, and if it's a neighbor next to them (Canada or Mexico) the blood shead could be high because of pupulated cities. As for money or a treaty it wouln't be that much of a risk but it depends on how much money and the details of the treaty.
It was that it didn't have a bill of rights, so I'd say "It did not protect the individual freedoms."
Lyndon Johnson is the president your looking for
The introduction of new predators to the insects' environment
Martin vizcarra is the president of Peru