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.
Wikipedia on 1930s pacifism: The British Labour Party had a strong pacifist wing in the early 1930s and between 1931 and 1935 was led by George Lansbury, a Christian pacifist who later chaired the No More War Movement and was president of the PPU. The 1933 annual conference resolved unanimously to "pledge itself to take no part in war". "Labour's official position, however, although based on the aspiration towards a world socialist commonwealth and the outlawing of war, did not imply a renunciation of force under all circumstances, but rather support for the ill-defined concept of 'collective security' under the League of Nations.
Why are you surprised at such stuff from the 30s? (There's similar stuff from the 1910s, the 1890s, 1860s and even that wasn't novel.)