This dispute, like others involving congressional demands for information from the executive branch, may end up in court. The law may support the director of national intelligence’s refusal to forward the whistleblower report to Congress. As an article in Lawfare points out, past presidents also have asserted a right to determine whether to share classified information with Congress.

For example, when President Clinton signed the Intelligence Community Whistleblower Protection Act, he issued a statement noting that the Constitution “vests the President with authority to control disclosure of information when necessary for the discharge of his constitutional responsibilities.”

It’s possible that a court will decide that Congress does have a right to see the complaint Maguire is refusing to turn over — perhaps in conjunction with the House Judiciary Committee’s impeachment inquiry.

But you don’t have to be a Trump supporter to worry about the precedent this would set for future presidents who want to be able to speak candidly to foreign leaders. That’s the problem with Trump: His trashing of norms of behavior that have been followed by past presidents means that future presidents may find it harder to do their job.