Trump is claiming public tax payor owned property is his.

[no_hypocrisy]

4. Generally beachfront property has a public easement on it, allowing non-owners access to the water.

What it sounds like is an attempt to gain ownership of the property via adverse possession.

It's like time-release trespassing with ownership being granted at the end of a period of time, either 10 or 20 years. You squat on the land in an "open and notorious manner", cultivate said property, and you are subject to being evicted by the true owner. Sounds like Trump's trying to privitize public property by putting beach chairs on the sand to give the appearance of possession and ownership.