Make recommendations to the united states about how to respond to hitler in the future

I believe there is no other way other than eliminating him directly.

In the past, the alliances made several efforts to try to persuade hitler to stop doing his extreme policies against various races.

But since naziism is a form of ideology, its followers tend to overlook several aspects of humanity in order to make their goals into reality. And all of it eventually ended up into one of humanity's largest mass murders