Why we don't fight with other countries

One of the reasons we don't just pick fights with other countries is because wars cost to much money we don't want to make more enemies we don't want to start fights at other countries and send all the soldiers there and have no defense here. Also we want other countries to be able to work there own problems by them selfs we might assist them with money or medical equipment and supplies. If things get out of hand then we might send our soldiers to help. Starting a fight with every country weakens America and other country's will stop supporting us.