Marines can't arrest the President.
First, Marines arresting anybody on US soil is a violation of the Posse Comitatus Act.
Second, any Marine arresting the President would be violating his oath of enlistment and the Uniform Code of Military Justice.
Third, the Constitution prescribes the only way for removing a sitting President -- which happens to be impeachment, not military coup.
Marines can’t arrest the President.
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I’m really not particular...
Make a citizen’s arrest yourself, if you like...