You are right. He didn't.
But after he took office in 2009, he filled his cabinet with like-minded intellectuals who's philosophies were quite clear, including Chu. Chu was hired because of his positions, not in spite of them.
And the social security payroll tax cut is a fraud. First of all, it's supposedly not a "tax", but a "contribution". It's hypocritical of Democrats and Republicans to decry the state of Social Security while voting to literally defund it.