The Spanish American War Soldier served at a time when the uniform was undergoing changes in material and color to adapt to tropical climates.

The 'campaign hat' was useful in all climates. It was not overly 'military looking'.
It appears to have become the medium for expressing one's individuality.
(Must have driven some officers and sergeants nuts, but, it probably allowed identifying a soldier at a glance)!

p.s. I would gravitate toward the Bugler's 'style' .... Fedora ... but, front of brim down & tipped to the right at a rakish angle ... if, you please.

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