Historically, the U.S. Marshals Service has taken responsibility for serving most Federal court criminal process.
Well I don't agree that they could act in this respect. He was sworn into office.
That makes him President in spite of how he got there.
He would have to be removed Constitutionally.
You can't just say, "nevermind", like Emily Litella.
Federal Marshals report to the Attorney General.
If Holder sent a directive down the chain of command that he would fire and prosecute anyone that attempted to act against Obama what would happen?
President Nixon ordered Attorney General Elliot Richardson to fire Cox. Rather than comply with this order, Attorney General Richardson resigned, leaving his second-in-command, Deputy Attorney General William Ruckelshaus in charge of the Justice Department. Ruckelshaus likewise refused to fire Cox, and he, too, resigned. These resignations left Solicitor General Robert Bork as the highest-ranking member of the Justice Department; insisting that he believed the decision unwise but also that somebody had to carry out the president's orders, Bork fired Cox. Upon being fired, Cox stated, "whether ours shall be a government of laws and not of men is now for Congress and ultimately the American people to decide."