What Makes Force Legitimate?

As we continue to discuss states' use of power and whether or not we consider them the rightful owners of force, it has made me question what makes a state's choice legitimate to both its citizens and the rest of the world.  I think this question goes back to a major point of our debate concerning the shifting norms of the global community and how approval from the rest of the world seems to be what we use a measure for legitimacy.  However, the way the world frames this question often has more to do with perception rather than an objective evaluation of the occurring actions.

When we observe Russia's actions over the last few years, almost no one considers these movements in the Ukraine to carry any level of legitimacy.  And we might say that in the modern international system we would consider any invasion of a state by another to be illegitimate.  But is that really true?  There is, of course, no perfect mirror situation, but it got me thinking about continued Western support of Israel while Israeli settlements continue.  There has been recent public statements of disapproval from the West by Secretary Kerry and the British Foreign Secretary, yet there is absolutely no discussion of retribution of any kind.[1]  Again, the situations are not the same, but there is the basic similarity of state-sanctioned occupation of a territory that is under dispute.   Why do we see one as illegitimate and unacceptable, while the other is merely objectionable?  What makes the difference?

I don't claim to know the answer to this, but it would certainly seem to me that this goes back to long-established traditions of cooperation and antagonism, with Israel and Russia, respectively.  Is that all it takes to shape the framework of an occupation or state expansion?  I found the recent article in Foreign Policy Magazine very indicative of many Western views of the Israeli settlements, in that it spoke mostly to the rate at which Netanyahu was approving is approving housing units.  As if the pace is the root of the conflict, rather than the fact that Israel is approving these settlements at all.  Putin offers similar reasoning for Russia's occupation in Crimea in that this is an area that should be part of his state based on culture and previous boundaries.  However, the West has soundly rejected these reasons.  I know these topics can stir up quite a bit of emotion, and I am not in any way comparing the leaders of these states or their actions.  I am simply pointing out that the way in which we determine legitimacy seems to vary based on how we view the actors involved, rather than the merit of the actions themselves. It makes me wonder how valuable our assessment of legitimacy really is.

1. Elliott Abrams and Uri Sadot, "Everything You Know About Israeli Settlements Is Wrong," Foreign Policy, September 5, 2014, http://foreignpolicy.com/2014/09/05/everything-you-know-about-israeli-settlements-is-wrong/