What's up with Liberals' memories?

It seems they cannot remember Obama making promises past two weeks ago but can remember all the way back to Bush from January 2009. What's with the blackout in memory-Stimulus promises vs unemployment, closing Gitmo, Obama Care lowering health care premiums, hope and change vs current welfare rates and foreclosures, ending wars vs starting a new one, government transparency, ending patriot act, etc. What do you call this kind of amnesia that forgets selective blocks of time?