In 1953, South Africans went to the polls. The South African government was run by the pro-apartheid National Party, but they were opposed by the more liberal United Party. A majority of white voters disliked the apartheid system, especially wealthy businessmen, and the United Party spent four times as much on campaigning as the National Party.
When the votes were counted, the results were clear: 54% of voters chose the United Party, rejecting apartheid policies. Yet, thanks to gerrymandering and other tricks, the National Party won 60% of the seats. In 1958, the National Party increased their majority despite still losing the popular vote.
Even though it had ‘fair’ elections, with a constitution very similar to Canada’s, the South African government was effectively a dictatorship. It rigged the rules of the game so no one else could win. Faced with an unchangeable government that supported terrible policies, wealthier South Africans did what they could: leave. The best and the brightest, the people who had made South Africa into the richest nation on the continent, started ‘packing for Perth’. Elon Musk – now worth about $7 billion, then just an ambitious teenager – was among them.
There are two options ahead for the US government. Behind door #1, politicians who support unpopular policies get voted out in primaries. (Third parties are not viable in the US due to Duverger’s Law.) If this happens, the government will – slowly and fitfully – move toward the popular position on a host of issues. Politicians, for all their faults, do care about getting re-elected.
Behind door #2, the Democrats and Republicans find a way to block candidates from primaries if they challenge the status quo. This is what John Boehner is currently trying to do with the Tea Party. (I don’t support Tea Party policies, but any kind of reform requires some way for a serious constituency to challenge party leadership, and I support having the latter generally.) If that happens, official US government policies will move farther and farther away from what voters want as culture and demographics change.
In addition, US policies will become ever less effective, as trends continue their progressions and conditions on the ground evolve. When current politicians were elected, in the 1970s, it was viable for the government to not know much about computers. Now, with Obamacare failing due to technical mishaps, it isn’t. It was viable for every student to attend college. Now, with exponentially rising tuition, it isn’t. It was viable for government employees to have defined-benefit pensions. Now, with Detroit bankrupt and all fifty states rewriting their retirement plans, it isn’t.
When that happens, if it happens, Americans will in their turn start ‘packing for Perth’. First in line will be those who can move most easily – the young, the rootless, the skilled but unemployed, the future Elon Musk (South Africa), Sergey Brin (Russia), Vinod Khosla (India), all those who in past decades moved to the US. When voting at the ballot box doesn’t count, when even voting in the primary doesn’t count, voting with your feet still does.
The Rationalist Conspiracy 
Musk moved to Canada in 1988. There are other reasons to leave the US other than a bad situation at home. There are many Europeans in Silicon Valley. Some prefer the politics of their home country but come because of quite specific virtues of the Valley (many of them not shared by the rest of the US).
The only issue is: If America ceases to be a functioning democracy, and a home for entrepreneurial culture, then there’s nowhere else to go. Perhaps Canada or Australia, but they seem more European in their orientation than American these days. Where would you go?