That's for the airline to offer, the passenger has nothing on which he can take any action against them. This won't stay on media for long either ways.
Firstly it wasn't an airline official who handled him as far as I saw in the video, secondly the security personnel would be permitted to use those means in the case of non-co-operation. So again, the bloke only has the media to put his "million dollar lawsuit" hopes on, and hope the airline care enough, which in general cases, they don't, in far worse incidents than these. As if people would suddenly stop using United to fly as long as they are competitive in the market and providing the fares they want.