"Military enemy" makes me think someone who was in or leading the military, which Hitler wasn't. The poll also exists in our real time line of Hitler and Kaiser Wilhelm actually being defeated, not what they might have done. I think the fear of them is lesser because of that.
Granted, I, too, think the poll result is odd, but mainly for the reason that I didn't think the British learned or cared that much about George Washington or held him in such high regard as to win a poll like this.
I thought I was going to hate the periodic table authors category because the description sounded confusing, but like a lot of people here, I ended up liking it quite a bit. Of course, my husband and I were tag-teaming it. I was throwing out the initials, and he was giving the elements. That made it fun for us.