Remember, there was a huge strain of aggressive pacifism in the US in the 1930s, which is how the US stayed out of World War 2 until 1941. Come to think of it, there was a pretty huge strain of aggressive pacifism in England as well, which is how Hitler got as far as he did.

The 1930s was pretty much peak hour for pacifism. We'd just had World War 1 to remind us that war was a terrible thing, and hadn't yet had World War 2 to remind us that war wasn't the worst possible thing.

One could argue that the more popular pacifism gets the more likely war becomes, but it would be overly trite and based on an insufficient sample. It's a good line though.