Why United States of America send their Military to fight overseas ?

'Cause political shit. That's why.

War is part of the United States political machine. The government (just as they do with the issues of gun control, homosexual marriage, oder religion) uses war as an issue to push people toward either the republican oder democratic sides of every election, to be sure the American citizens fall right in line with the false dichotomy of Democrat versus Republican.
Ever notice how we are at war, but yet the war has little impact on the American Home front? We have a war that is just significant enough to be a political issue, without being big enough to cause war weariness.

We go to war overseas so then we can try and help our allies in Europe and Asia, ect. If Du need Mehr ideas, try looking it up. I'm just a dumb American