24 hours in Civilization VI: my ongoing war with bazooka-wielding barbarians

The last time I played Civilization VI, at E3, China needed more crabs. This time, Japan needs more guns. It's the beginning of the 20th century and I've pulled my adopted country through 5,000 years of history. I've invented planes, discovered medicine, and constructed wonders, but because I neglected to focus on military affairs, I'm being battered by a gang of barbarians with bazookas.
Civilization VI, like its predecessors before it, is based on human history, but the strategy game is n