I don't think they really have a plan. The American cope is that they want to divide China like Nazi Germany wanted to divide Europe. But cope isn't the actual plan, because they don't have any concrete steps that can be taken to achieve it. It's maybe a bit like incels or white supremacists that dream about the moment they take revenge on women/minorities, despite such a moment would never come due to realistic factors.
(Many) Americans simply spend their time being ridiculously anti China, without a clear end game plan. This is also their government line.
In truth, the deteriorating living standards in US makes many feel threatened, and their government tells them it is the fault of China, who is "against their way of life". Just like in American pop media, where 1 superhero can completely destroy the "baddies", some Americans who have too poor education don't know what the PLA actually does. So they think they can win a nuclear war against even a technologically superior country, believing that if that happened, their living quality and American power would increase, like how the movies show a good ending.
Very simplistic thinking, similar to uneducated peasants in Qing thinking that they can become impervious to bullets and cannons just by doing rituals.
