Trump is too arrogant to be a puppet president, especially for a cause that he doesn’t believe in. For that to work, they would need some way to control him and now he cant be charged with any crimes blackmail isnt an option. If they push him too far he might use Putin’s playbook and have people accidentally fall out of a window.
Where do you draw the line? If you are happy to give up Ukraine to avoid a nuclear war, where do you stop? Can he take all of Eastern Europe? What about the whole of Europe? Everywhere except your country?
Putin is a bully, and you stand up to bullies.
Besides, he might have the most nukes, but given the maintenance costs for 5,000+ of them and the corruption in Russia, most of them probably won’t work.