Actually it's not the military's place to impose or enforce domestic laws. Case in point is posse comitus. The military is not in the business of "policing" it's own unless in EXTREME cases where available resources are inadequate(ie national guard call outs). Domestic will be where the FBI, FEMA, local police departments, etc come into play. Foreign policy will be the military, CIA, diplomats/ambassadors. The military should always be held in check so that there never is a situation where the military "usurps" the authority of the people (ie military overthrows the government). We don't want military rule, ever, unless in dire crises and existing civilian channels are closed or ineffective. Then and only then should the military TEMPORARILY step up to the plate. The moment the situation stabilizes control should be promptly handed back to the civilian arena.
Short of that, the military is not to impose policy on it's own citizens. Actually it's exactly the opposite. The military is to follow the policy set by the civilians.
Keep in mind that the military members are also voting members of the public, which allows their voice into that policy development. That's their "in" for input on how their own organization should be run by shaping policy from the civilian side. Hot topics that are being debated by the population for implementation within the military (somewhat recently) are: women in the military, environmental impacts, nuke arsenal capacity, etc. Currently being debated in our society, some topics include: homosexuals in the military, women in combat, non-lethal weaponry, etc.
The best way to describe the point is to take it to an extreme---
If the majority of the civilian population wants to disband the military, guess what, the funding dries up, paychecks stop, and the military disbands (albeit grudgingly and complaining the whole way). The realization that the public MUST recognize is that by taking that step the next time an attack happens or there is a need to project power into a hostile area there will be NO trained people, organization, equipment to deal with it. The situation can be overcome though, but it's cost will be measured in lost life and blood that exceeds what would have been experienced had the military been maintained. That's even without bringing the money factor in.
Anyway, bottom line is (not to sound like a skate out but) it's not the military's job to start shelling congress just cause they legislate a bad law. The system allows mistakes (hopefully fewer than other comparable systems) just like prohibition (sp?) where alcohol was outlawed (remember dukes of hazzard?). The majority of people came back and said "That's stupid! Change it!" and it changed back. That's the flexibility of the constitution! We in the military took an oath to protect the constitution and its values. If we disagree with legislation or laws we VOTE to change it (or the people in positions to influence) and meet the spirit of the oath by exercising CIVILIAN rights.
Brian