The Pentagon's pissed off at a new LGBTQ-focused military series ... claiming it goes completely against the "warrior ethos" -- and, they're bashing Netflix for it. Here's the deal ... the show "Boots" -- the story of a gay Marine recruit, forced to hid his sexuality in order to serve in the 1990s due to the "Don't Ask, Don't Tell" policy in the military -- debuted on the streamer just last week, and it's pulling huge streaming numbers. The show's still sitting atop the chart for the company ...