This is Martin Lewis, who writes,

General Pace -- you have the power to fulfill your responsibility to protect the troops under your command. Indeed you have an obligation to do so.

You can relieve the President of his command.

Not of his Presidency. But of his military role as Commander-In-Chief....

In addition to relieving him of his command as Commander-In-Chief, you also have authority to place the President under MILITARY arrest.

Read the whole post for more details, and for Mr. Lewis's statement, "To be crystal clear -- I am NOT advocating or inciting you to undertake any illegal act, insurrection, mutiny, putsch or military coup." So you're urging a general to arrest the President, and at least to strip the President of his constitutionally assigned role as Commander-in-Chief, but "[t]o be crystal clear," you are "NOT advocating or inciting you to undertake any ... military coup." Oh, OK.

(I take it that Lewis's defense would be that the general's actions wouldn't be a coup because they are authorized under military law. But the military's displacing civilian government in a way that is nowhere authorized by the Constitution -- which is quite explicit both about the President's relationship to the military and about the ways that the President can be relieved of command as Commander-in-Chief -- is surely a coup, even if you've come up with a creative reading of the Uniform Code of Military Justice to try to support it.)

I don't agree with Clayton Cramer's suggestion that Lewis's speech is criminally punishable -- the Constitution trumps the statutes that Cramer cites as well as the statutes that Lewis cites (though at least Cramer's argument is much more plausible as a statutory matter). But surely public calls for a general to oust the President should be pretty firmly denounced, even though they shouldn't be criminally punished.