You don't seem to understand that we have civilian control of the military. And, that civilian control is decided by a political process. The political process elected Barack Obama. The military has absolutely no role, right or in questioning that political process.
When is the 20th Amendment ever designated to political forces (i.e. Congress) to enforce?
This is a JUDICIAL issue, not a political one.
You don’t seem to understand accepting illegitimate orders and killing people is a criminal and immoral act.