Obama has recently declared that Awlaki the imam who was associated with both the Xmas bomber and the Fort Hood major who allegedly shot a number of troops can be killed and is a lawful target. As this short passage shows Obama was highly critical of Bush's view that he could even jail an American citizen without charge as an unlawful enemy combatant. What a difference being in power can make! This is from Salon.
5. Does the Constitution permit a president to detain US citizens without charges as unlawful enemy combatants?
[Obama]: No. I reject the Bush Administration's claim that the President has plenary authority under the Constitution to detain U.S. citizens without charges as unlawful enemy combatants.
So back then, Obama said the President lacks the power merely to detain U.S. citizens without charges. Now, as President, he claims the power to assassinate them without charges. Could even his hardest-core loyalists try to reconcile that with a straight face? As Spencer Ackerman documents today, not even John Yoo claimed that the President possessed the power Obama is claiming here.