Abravnel’s pictures show two bearded men wearing sunglasses and three other men wearing face coverings on board the boat. One of the men on board appeared to be holding an image of Mike Lindell, CEO of the My Pillow company. Lindell, who is a well-known Trump supporter, recently hit back against claims that his product pricing was inadvertently linked to neo-Nazi propaganda.
IANAL but I looked into it -
In the US, political signs are considered private property so you could get arrested and charged with vandalism (if you get caught).
It’s unlikely you would be charged with trespassing (since that usually requires multiple repeat offenses on the same property).
It’s probably something you could beat in court as long as you don’t talk to the cops during your arrest and pay good lawyers.