Slightly off the current tack of the thread, but I'm kind of bemused by the folks a few pages back who are convinced that Canada joining the US would dramatically sway US politics. Canada's estimated population in 2011: ~34 million. US population at last census? 308 million. Essentially you'd end up adding Ontario, Quebec, British Columbia, and Alberta as moderately influential states, and everything else would be on the same level as North Dakota and Alaska for political influence. More people live in California than in all of Canada.
I suppose it's possible that Canada is just so liberal that it skews the power balance. I don't know.
The addition of Canada as three or four states would be enough to sway the following presidential elections into the democratic column: 2004, 2000 and maybe 1968 (electoral college deadlock would have lead to the democrat controlled house picking the president)
Half of the republican controlled senates of the past 30rd years would have been democratic controlled senates.
If it shifted the control of the house by just 5.5% towards the democrats (not unreasonable, considering that Canadians would be 1/10th the population and the median Canadian is the left of the democratic party), the republicans would not have held control of the speakers gavel for more then the past 60 years. During the 80th congress, the GOP would have held the gavel by a sliver but Truman would have been reelected by a comfortable margin. The signature legislative accomplishments of Nixon and Regan never would have made it through congress and Bush Jr. never would have been president.
Some changes in legislative history that such a shift would entail:
Medicare would apply to all citizens, not only the retired (just like Canada
) That's assuming that Truman wouldn't have been able to pass single payer in the early 50s
There would have been no Regan tax cut and probably very little national debt today
The Civil Rights act would have passed about a decade sooner
Cap-and-Trade legislation for carbon emissions would have passed in the last congress
President Gore would not have invaded Iraq
Financial Regulations with actual teeth would have passed after our recent economic meltdown, assuming there would have been a meltdown without the wave of deregulation that started with Regan
The Federal Reserve would have been given sufficient political backing to greatly reduce the severity of our current downturn, instead of being hampered by a bunch of born-again austrians on the board of governors who claimed to fear inflation in the middle of a depression (give me a break!)
Of course, there's the whole butterfly effect. But saying that Canada's population is "only" 1/10th of the US's is quite silly given the extreme tipping point nature of democracy. If you shift the partisan nature of the US only a few points in the left direction, you've got enough votes for the country to be a mainstream social democratic country just a little right of center like England. Tiny shift at the margins matter a lot.