The Canal was not freely given to Panama to do with as they wished, there were contractural agreements put in place, touched on in that link.
It is absurd to say that Trump has no right to insist that Panama uphold their end of the bargain.
Trump claims that as the US built the canal with their blood and money [I would challenge the nationality of most of the dead, but that is not the argument] China is not entitled to take over at the price of a few trinkets.
Typically inconsistent, the LWNJs insist that Panama has the right to extort the US on passage fees even though it causes inflation in the US, inflation that would be worse if passage was denied, but Trump is not entitled to raise tariffs because that would be inflationary. Figures.