Consider this. If you made a sign or banner saying Hillary should be jailed, took it with you to the front of her headquarters and a member of her security snatched it from you and walked away with it, would you consider that theft? I believe most people would.
These same people who are attacking you and me would be OUTRAGED and demand prosecution. I'm a Trump fan, but I think this was a stupid move by the guard. Obviously the sign wasn't blocking the path because he apparently was the last of the entourage to enter the building. Everyone else apparently managed to get through without stealing the sign.
Nope. I would not consider it theft and I wouldn’t be stupid enough to tackle an armed security guard over a piece of cardboard. Use your head for gosh sakes.
And if I was blocking an entrance to private property and preventing people from entering I would expect that my sign may be taken and I would be asked to leave. Your first amendment rights end on private property. And you have no right to block people from entering buildings.
Odds are this person with the sign isn’t even here legally so as far as I am concerned they have no rights at all if that is the case.