I'm not sure that being shamed (if that can happen to Mr Tump) into being a co-signer of a letter indicates the emergence of any global matter on Mr Trump as it relates to his buddy Putin. Ms Haley was ahead of the curve that Mr Trump seems to be clinging to after the fact.
"A pessimist sees the difficulty in every opportunity, an optimist sees the opportunity in every difficulty” ---Sir Winston Churchill
"Political extremism involves two prime ingredients: an excessively simple diagnosis of the world's ills, and a conviction that there are identifiable villains back of it all." ---John W. Gardner
“You can’t go back and change the beginning, but you can start where you are and change the ending.” ---C. S. Lewis