Given that he was nominated to the post by the Obama administration and confirmed by the Senate, where should a grassroots movement to get him shucked out of office be directed?
Towards rejecting the entire autonomous bureaucracy he is but a small part of. However, given that most of the US is contentedly employed in service of the top-down government, agorism is the best bet.
Lawsuits against bureaucratic offices is a good place to start. I wonder how much royalty-free software they use that has methods patented by someone else?