Reiterating a hard-line nationalist approach, Mr. Trump raised new questions about his commitment to automatically defend NATO allies.

NATO was born in a time when people learned the hard way that they cannot battle the cruelty of life on their own. States have the obligation to help one another for the purpose of safety. It is not conditional. To make it so, tells our allies that we are better than them and that they don’t deserve our help, when in fact we are just a state, and because of that, they deserve our help as much as we deserve theirs.

Plus, creating discord within NATO and furthering their suspicions of our interest, especially after Brexit weakened the EU, hurts a major intercontinental alliance- a symbol of mutual respect and interdependence.

Mr. Trump repeatedly defined American global interests almost purely in economic terms. Its roles as a peacekeeper, as a provider of a nuclear deterrent against adversaries like North Korea, as an advocate of human rights and as a guarantor of allies’ borders were each quickly reduced to questions of economic benefit to the United States.

We can’t expect other nations to have respect for us if our policies continuously bully our supposed allies for our own benefit.

Source: Donald Trump Sets Conditions for Defending NATO Allies Against Attack