When you really sit back and think about the obstruction Obama faced over the policies he pursued, you find yourself falling back on the same reason over and over for why Conservatives would suddenly oppose things they supported for decades. There is only one constant; Obama's race. Obamacare was based off Romneycare, which was based off the Heritage Plan. Cap-and-Trade was a Republican proposal. Tax cuts are the fundamental dogma of the right, yet they opposed the payroll tax cut.
We see over and over the same pattern; a black guy proposes something that Conservatives previously supported, so they reflexively oppose it.
That's because they're racists. There is no other explanation that makes any sense.