Politifact takes issue with President Obama’s State of the Union discussion of Citizens United.
Indeed, the legal experts we spoke to after Obama’s radio address said that the president was overstating the immediate impact of the opinion. They said Obama was correct that the ruling could open the door to foreign companies spending on American campaigns, given the general direction of the majority’s opinion. But because the majority justices didn’t actually strike down the existing barriers on foreign companies — in fact, they explicitly wrote that it fell beyond the boundaries of their decision — our experts agreed that Obama erred by suggesting that the issue is settled law. Until test cases proceed and further rulings are handed down, Obama’s claim about foreign campaign spending is a reasonable interpretation, and nothing more.
The Post has some more analysis here.
Then-Senator Obama voted against Alito’s confirmation to the Supreme Court and I believe Alito has made remarks over the bitterness surrounding his confirmation.