Yes, he's immoral, unethical, dishonest and divisive, but the character fault that most imperils the USA and our allies is his irrational belief that he is always the smartest person in the room. Witness the Helsinki fiasco, when he not only disgraces our own national intelligence community in front of our most potent enemy, but then "doubles down" by positing a joint effort with Putin to create a global cybersecurity effort. And who knows what he said in his private conversation to further erode our national security.
He discredits the FBI, the CIA, the world scientific community, NATO and the EU. He seeks to legitimize murderous, wealthy autocrats like Putin, Saudi Prince bin Salman and Kim Jong-un by taking each at their word. I think he wishes he could be as unfettered as they by the U.S. Constitution.
He fires Gens. Kelly and Mattis, and allows Haley to depart, leaving a vacuum of those in his administration committed to America, as opposed to Trumpism. The voices of reason in this administration are becoming extinct. We are left with the likes of the greedy (Ross, Mnuchin, et al.) and the vacuous (DeVos, Carson, Sanders, et al.).
After more than two years of his bluster and political puffery, here we are: Russia has solidified its reach in the Middle East and eastern Europe; genocidal Assad is so firmly back in power in Syria that he dares travel to Iran (I predict Moscow is his next foray); China is extending its influence throughout Asia, Africa and South America; North Korea still has nuclear weapons capable of reaching the U.S.; the Taliban is re-establishing its dominance in Afghanistan; and the Doomsday (nuclear countdown) Clock is at its most dangerous point since the mid ‘50s.
Meanwhile, Trump declares his wall to be a national emergency?
If Senate Majority Leader McConnell doesn't start to exercise legislative oversight and do what's right for the country, by the time of the 2020 elections it could well be too late.