If our government is on the brink of default, what is the argument for military involvement overseas?

Given the fact that our economy is in such bad shape, is there any OVERWHELMING argument for our continued spending of immense amounts of money to continue our military involvement in the Middle East, for example? There have been warnings lately that if our government does not improve its credit rating, etcetera, that social programs like Social Security, Social Security Disability and VA benefits might be cut, leaving many people in very desperate straits. The very wealthy, of course, would not suffer. It seems there are things that could be done which would not leave the most economically vulnerable to hang out to dry, and curbing military spending might be a viable first step. Is it time for the U.S. to adopt a semi-isolationist policy for awhile until we can get our own financial house in order? Doesn't "charity" begin at home? What about taking care of our own for awhile and easing up on our military activity overseas???