Earth is already a spaceship. The problem is, we have no control over where it's going.
The famous inventor and architect R. Buckminster Fuller has already written a (sufficiently loony) essay/book about this in 1968:
Operating Manual for Spaceship Earth.
It has pirates in it, too. And the original coining of the word "synergy". But it is much weirder than you may think (IMHO).
In fact, at this point it looks like the vast majority of congress, regardless of aisle position, and the white house didn't really know the extent of what was going on.
That means, that in the USA there's an organization (NSA) with a budget of billions, with no effective oversight, that specializes in (industrial) espionage on everyone in the world.
As a European, I feel so much safer now!
If he did, the Republicans would then claim that Obama is deliberately sabotaging the NSA and jeopardizing national security. To the Republicans, every move Obama makes is wrong, no matter what move that may be.
The Republicans? Oh yeah, that was some kind of political party in the 20th century; like the Whigs. or was that the 19th.
Variables don't; constants aren't.