To have principles is to be under obligation and responsibility. The 18th century Westphalian philosophy of "sovereign" nation served a specific purpose within a context of ending the Thirty Year's War and limiting imperial power. The modern world has no emperors or singular superpower to dictate universal policies. The modern world lives by moral relativism, which you champion, under which all national actions are beyond reproach, even "violation of sovereignty."

The premise of "sovereignty" is based upon the assumption that nations have some "right" to exist. Nation-states are arbitrary creations of 19th and 20th century political convenience. Nations have no "right" to exist. If you believe in the "rights" of nations to exist, then why aren't you demanding the reconstitution of the USSR, the Ottoman Sultanate, or the Austro-Hungarian empire? Nations have "sovereignty" over the regions they can project authority. Syria is no more than areas around cities to which Assad can project power. Since the 'Muricans can project fair degree of power across large swaths of the globe, the areas under which 'Murica can project power are its "sovereign" territories.

It is the same with "personal" rights. From whence do men imagine they derive their "rights" to exist? In a world, in which there exists no principles, no man can claim any "rights" that which he can not personally wrest from the clutches another.