They could publicly denounce Israel all they want. It would be meaningless. What a non dual citizen law would do it make it clear that politicians are supposed to be loyal to the USA and not some other countries. If there was enough support to have that law passed people like Senator Chuck Schumer would have to stop loudly and proudly saying they support Israel first. People might start demanding a good reason for all the money and resources sent to Israel every year. They don’t just need to fight non dual citizenship laws. They need to fight whatever might cause people to support these laws. That is the real danger to them.