[weinzierl]

Is 52 a typo or did he really say that? The US has 50 states, so why not 51?

[mcherm]

I suspect that the implication in context was that the 51st state would be Greenland. Which doesn't really help make this less of a diplomatic faux pas.

[bemao]

Probably a reference to the "joke" that Canada would soon become the 51st state

[simiones]

Maybe his views are more heterodox and he was counting Puerto Rico as 51st! (sarcasm, in case this isn't clear)

[csomar]

Greenland is the 51 state.