The worst legacy of Mr. Trump is his statement to the world that the American System does not work.
He has shown that our system permits a President to renege on the word of previous Presidents, himself included. Treaties signed can be revoked. Trade deals like the USMCA, negotiated and signed by Mr. Trump can be thrown away by the President who negotiated and signed it.
Paris Accords. Not anymore.
Iran Nuclear deal. Not anymore.
Trade Agreements with Asia, India, Turkey. Not anymore.
Commitment to the poor and sick who need help. Not anymore.
Keep the uninformed informed through the Voice of America, Radio Free Europe, or Radio Liberty. Not anymore.
NATO. Not necessarily.
The UN. Not necessarily
Nor the WTO, the World Court, or the WHO.
The world now understands that the American system of government and its international declarations cannot be guaranteed to last even a week and can be tossed aside on the whim of a President. Even Congress cannot enforce those agreements.
It is easy to throw trust away. It is far, far more difficult to rebuild it. Mr. Trump is showing the world the American Way, and it is not what we have always believed it to be.