Never refer to a Marine as a soldier. It's considered a slur and an insult. The Marine Corps has Marines. The army has soldiers. So endeth the lesson. Semper Fi.
Soldier, like Marine Sailor or Airmen is capitalized.
Well call me soldier.
I was in the Navy.
But yeah, good point. I’m sloppy when tired.
That's one of those things that leads me to discount anything else that person may say about military culture, etc.. If you aren't familiar with the basic distinction between "soldier" and "Marine", then you lack the requisite background knowledge to have an informed opinion about the rest of it.
Semper Fi.