The "Founding Fathers" worried a lot about the effect a large standing army could have on their young democracy. They had just endured occupation by English and Hanoverian troops and fought a revolution to throw them out. And history had shown that a large standing army was as likely to be used to oppress its own people as against foreign invaders. To ensure that this did not happen here, the Constitution envisioned a system of state militias that could be called into federal service to meet a common threat. In case of an impending major threat or for continuous needs, such as manning frontier posts, Congress could authorize an army, but could fund it only for a period of two years.

We don’t worry much today about military coups in the United States, and rightfully so. Yet, even after post-Cold War downsizing, our armed services consist of millions of uniformed personnel and millions more civilians, reservists, retirees, and employees of companies who derive their income (directly or indirectly) from the Department of Defense. These people, like any other group in our society, organize to influence the political system.

Eisenhower's famous caution is worth repeating:

This section of Defense and the National Interest examines the effects of the defense establishment on the larger society and the methods the various players use to help determine political outcomes in their favor.