Exactly landmass and coastline will trend towards 0 with enough sea rise.
And looking at a topography map of the US specifically the amount of coastline that could possibly be gained (if any) would not be worth the trade-off of losing pretty much all of SE US. Trump is definitely an idiot.
I accuse you of sending billions of dollars in military aid packages to Ukraine!
...Uh yeah, it wasn't a secret.