SA
Because it reveals the trajectory the country has taken since the toppling of the old regime. Has Serbia since 2000 been a perfectly compliant client state of NATO, the EU, and the United States? Certainly not. There was an assassination of a pro-Western Prime Minister in 2003, opposition to the independence of Kosovo, and continued nationalist sentiments in the country. At the same time, there can be no question that the current government is more friendly to the U.S. and Europe (formal application to the EU was made in 2009) and to Western multinationals than the Milosevic regime.
This has been the pattern again and again in these regime changes. The new governments are rarely literal puppets - but then many colonial regimes would not even have qualified for that distinction. But they have been more pro-Western and neoliberal than the governments that came before. The corollary is that these regimes, regardless of their degrees of autonomy, never seem to be more progressive in terms of economic policy than the governments they replace.
We have a pretty good sample size in the post Cold War period. I'm not sure why we need to pretend that no intelligent forecasts can be made about Libya. America's foreign interventions are about as predictable at this point as Hollywood action movies. And like the movies, they serve as a reliable form of popular entertainment and spectacle for the Western masses.