One ought to meditate upon the recent events at Fort Hood, Texas, and who we allow into our military.
All military personnel swear an oath to defend the Constitution from all enemies, both foreign and domestic. The Constitution is a document that not only limits government, but establishes equality of all people before the law.
While this is not to paint a broad brush against those who subscribe to certain tenets of the Islamic faith, it does pertain to those who support the institution of Sharia law. Sharia law considers women to be inferior to men, with few rights, as well as all people who are not Muslim. Many believers also subscribe to violent overthrow of constitutional government to reach their goals. Such individuals consider it ethical to lie to reach what they consider to be noble ends.
Such people cannot be trusted to uphold the Constitution if there is evidence they believe in Sharia law, any more than we could trust Nazis or communists to do the same. We need to enforce constitutional oaths far more vigorously and eliminate such dangerous people entering the military.