Addendum:

I forgot about this, we also have all the significant ports. The East Coast is less thoroughly liberal than the west, but Mike is right about the move to the right being less severe as you head west from NYC. So even if we couldn't hold the east coast as convincingly, that's not a big deal, all the good shit comes from China and SE Asia anyway, one well-placed bomb to the Panama Canal and the conservatives would be in dire straits. They'd have to head south around Argentina y Chile, and I'm betting there are tens of thousands of REI Lifetime Members who know Patagonia like the back of their hands. I see them riding Guanacos across the tundraed plain, stark, craggy mountains rising in the distance like a tide of blue doom. Their light sabers wildly aglow in the half-light as superstitious Chinese sea captains turn back their charges, returning to Shanghai half-crazed, babbling about the man-demons riding furry horses bareback through South America. No, they'll have to find another way to exploit China's cheap labor force, the penguins and llamas are on our side.

Don't worry about Canadian ports, they voluntarily chose universal healthcare--they're on our side by default, especially those in BC. Siding with the Conservatives would eventually lose them their unofficial cash-crop, Marijuana.

Smuggling things via the ol' silk road through Europe wouldn't really work for them either as the conservatives have been bitching for YEARS that Europe is more or less communist (utterly without merit), and we all know how much animosity comes from the mainland of that continent focused directly at one George W Bush. I don't think we have to worry about the Arabian Peninsula for reasons that don't need explanation. That leaves them what, India? A slow boat 3/4s of the way around the world from China? Not likely. And we can get South Africa if we need to, Mandela is a HUGE Che Guevara fan, he can be turned.

Oil could be tough, though. We'd have to secure Alaska right-quick, then put the scientists to work on alternative fuels--and light sabres.