Possibly, but the *Dewey Canyon II* Demonstrations in Washington weren't until April, 1971, in response to the then-ongoing *Dewey Canyon II* incursion into Laos. Jan Michael Vincent's made-for-TV anti-war/USMC production Tribes [with Darren McGavin as the Marine Drill Instructor] aired in the US on 10 November 1970.
That's a long time to go without a shirt, even for Janny-Mike.