I think you mean NATO. Ukraine is already in the UN, and gets no real protections out of it.
If we ever gave Article 5 protections to Ukraine, we should definitely let them into NATO. They have experience and knowledge that would be a great addition to NATO. They certainly are willing to put up a defense of NATO.
It is the if that is a problem. Obviously, while they are being attacked, we will not give them Article 5 protection, because we do not want to go to war with Russia. trump will not really ever give them Article 5 protection, because he would never be willing to defend them over Russia.