Tl;dr Included at the bottom of part II!

As I have harped on in numerous other posts here, US religion and war are inextricably interconnected. And this case is no different. Following the Spanish-American War, the US had established itself firmly as an imperialist player and a great power. Internally, religious liberalism was becoming a dominant political force: the excesses of the economic explosion that followed the end of the Civil War had reached their high-water mark by the 1890s with the so-called Robber Barons you probably remember from APUSH, if you’re American and your high school was College Board-inclined. Money was incredibly concentrated (with economic inequality numbers akin to, or by some measures better than, today, for whatever that means) and populist movements were springing up, especially among farmers and factory workers. The Progressive Movement (capital-P denotes specific to this period, lower-case to the broader, ongoing idea) and the Social Gospel are two wings of the same religious-political movement. And they were responding to the pressures of modernity.

America was rapidly industrializing and cities were exploding. Americans, namely men, of the time looked back and imagined (because just how true their nostalgia was to real life is debatable) a past where men forged through the frontier (often painted in feminine language, including as virginal). They were their own masters. They hunted wild animals and took from the earth what they needed. They protected their families from the elements and the brutal savage, who was, contradictorily, also painted using feminine language, which I will briefly circle back to shortly. The encroachment of civilization had domesticated man, made him weak and servile.

So, you can imagine how the figure of Teddy Roosevelt was appealing, from his Rough Riders gallantly winning the Spanish-American War, to his manly hunting of giant wild animals but also his paternalistic protection of the (remember, feminine) remaining bastions of nature. And indeed, Roosevelt was himself a Progressive who pushed men to aspire to a “strenuous life” (in an eponymous 1902 speech) that would protect and assert the manhood of the United States at home and abroad. He directly tied national pride to masculinity, arguing that the greatness of a nation was found in the character of its men, who paid glory to God thereby. And this “crisis of masculinity” was deeply religious as well.

The 1800s saw cycles of evangelical revivals that rocked American culture. Evangelical Christianity was depicted as direct, emotional, sensuous (not sexual but merely “of the senses,” i.e. not “purely” intellectual), sometimes ecstatic experiences of God. Straightlaced New Englanders and other Mainline Protestants looked askance at what they characterized as deeply feminine and uncivilized (as you’ll see, an extremely recurrent theme in US rhetorical history) Christianity. Protestants in the US had long characterized Indigenous cultural-religious traditions (the very idea of a separate “thing” that’s called religion is wholly alien to the vast majority of indigenous epistemologies and is chiefly a Christo-Muslim contrivance) and Catholicism in feminized terms: they were sensuous (again, not intellectual) and their followers were silly fools tricked by medicine men/priests. They lacked the intellect, independence, and refinement that characterized men, and thus they resembled women, who were easily taken advantage of, subject more to the senses and emotions than to the written word and the intellect, and less in control of their faculties.