Old school vs. new school:

Former NATO supreme allied commander Adm. James Stavridis, writing in Foreign Policy, says the alliance has to act now on Crimea.

He suggests NATO increase its intelligence-gathering and sharing, advise Ukraine's armed forces on how best to confront Russia and develop contingency plans for direct involvement, backed up by the stationing of naval forces in the Black Sea.

Meanwhile, Stavridis' successor, Air Force Gen. Phil Breedlove, tweeted this on Sunday:

Now retired, Stavridis is free to say what he really thinks, while Breedlove is pretty much limited to giving the official position of alliance leaders. Still, it's a stark contrast.