Hi, I'm Heather, an attorney with 15 years experience. I'm so sorry this is happening to you. It sounds like a terribly difficult situation.
First, you cannot let yourself be controlled by this person. Under no circumstances should you go to Ukraine to meet him. You could find that your life is in danger.
If he posts the photos, then you will have to deal with it when it happens. Facebook should cooperate in helping you remove them, and in deactivating his profile, or subsequent profiles that he sets up if he tries to post them. But you will have to wait and deal with it when it happens.
I'm not sure why he says you violated the Patriot Act, but he certainly is not in a position to tell you whether or not you have violated it, or whether or not you would be prosecuted.
This all really sounds like a scam to me, and meant to threaten and intimidate you. Try not to give him that control over you. If he tries to post the photos, you will deal with it. But until then, you should just sever all contact with him and live your life and be the best mom you can be.