Our rights as Americans are defined by the Constitution. Any threat by these rights are affirmed by federal courts and the Supreme Court. The military does have the duty to defend the Constitution, but we haven't gotten to that point in a long time. The military defends our international interests. A soldier is not going to defend your first amendment privilege, it just ain't gonna happen.

And most of our defense is currently paid with debt. The taxes you pay are barely paying the interest on our debt, let alone the principal.