If it's fair game to do this in Venezuela, it's fair game here in the US.
And to be fair nearly happened in July 2024 as the last item of a long list of incident involving U.S. Presidents starting from Lincoln all the way up to the July 2024 episode and of course the last successful hit being JFK in 1963 and the last successful injury being the one suffered by Ronald Reagan
There is no "fair game" in geopolitics
That's not really how power works