Robert E. Kelley lists the top 7. Canada and Mexico are tied for first:

Yes, Mexico is vastly more important to the US than Israel. However, the rest of Latin America, including that now-pointless embargo of Cuba, really isn’t. How damaging has Chavez really been to the US? Honestly, if we were really strapped for cash and over-committed, we could cut the Monroe Doctrine loose. Latin America doesn’t really need us or the fairly condescending ‘Roosevelt Corollary’ anymore. Strictly speaking, Canada does not need America commitment; Mexico does somewhat. But proximity alone means they are America’s most important allies. We can’t retrench from North America.

He follows up with a list of 8-11 and a longer justification for the rankings. This strikes me as the kind of truth you don't often hear in Washington:

America’s national security interest in Israel is not particularly obvious now – the Cold War is over, S Hussein is gone, Assad is on the ropes. Nor is it clear that Israel really needs us. It needed us to survive the Yom Kippur War, but now? Its got the best military in the region, plus nukes. The real ‘values’ link between Israel and the US now is more tribal (a Judeo-Christian struggle against Islam) rather than liberal.