It was, in fact, predicted by some. In 2007 when Barack Obama was but an ambitious Illinois senator, American defence expert Kori Shake penned an essay called the Coming Crisis of High Expectations. It was about how the EU and the US would inevitably slide apart - but its message was broader. Beware of exorbitant expectations, she seemed to be saying. Reality hurts.
How much it hurts will become clear today. It looks like a House of Representatives-sized hurt but not a Senate-shaped one. Harry Reid clung on to his Nevada Senate seat, and California will be Democrat-run. But the Republican Party succeeded in many other places - with the Tea
The most interesting thing to watch will not be the size of the pain but how the US president deals with it. Bill Clinton was a left-wing pragmatist, able to change when he needed to. Barack Obama is a pragmatic leftist. He may struggle to set a new course.
The other challenge will be John Boehner's. Just as Democrats had unrealistic expectations of what Obama could achieve in 2008, now many Tea Party activists expect a lot from the new House Speaker - that Congress rolls back the state, jump-starts the economy and de-constructs Obamacare.
But to succeed - and avoid a Newt Gingrich-style close-down of the US government - the Republican leadership will have to collaborate with the Obama administration. That will not be welcome to many Tea Party activists - who will be happy to unleash as much hurt on their own party as they inflicted the Obama administration.