If Mueller can’t get the answers he wants, he will have to decide whether he’s ready to test his power to issue a subpoena for the president’s testimony. Mueller’s prosecutors reportedly have made the threat before, but now the step comes with the added wrinkle that it could spark an internal Justice Department riff with his new supervisor, acting Attorney General Matthew Whitaker, who previously has been critical of the special counsel’s investigation.

Should the special counsel win DOJ approval and pull the subpoena trigger, he’d still have to face off against a president who has relished taunting Mueller and enter into a legal battle that could quickly elevate to the Supreme Court, where a newly enmeshed conservative majority is widely seen as friendlier to Trump’s arguments.

Round Two of Mueller versus Trump could also fizzle, though.

Legal experts say that the special counsel might have enough information from documents, presidential tweets and witnesses to wrap up the obstruction of justice portion of his investigation and file a report to his DOJ supervisors — all without forcing a court showdown just to nail down an interview with the president.