[Alberta's Child]

I suspect the Nixon administration was reluctant to prosecute these people because they knew they couldn't possibly keep a straight face in court when a defense attorney asked them to explain what meaning the word "enemy" has in Federal treason statutes in the context of a military campaign that was undertaken without meeting even the most basic formal requirements of the U.S. Constitution.

[Interesting Times]

I doubt that had anything to do with it.

You'll recall that U.S. spies were convicted of treason during the Cold War, despite the absence of a formal declaration of war against the Soviets...