In this particular case, when the person involved is both a Canadian, and a Native American, how could it be relevant to use the term "patriotism" in relation to the United States anyway?

No shortage of Americans killed by "friendly fire" - here's a site that gathers details AMERICAN
FRIENDLY-FIRE NOTEBOOK. Nothing on recent wars, but for the last Iraq war here are the figures:

"During the Gulf Campaign (1990-91) approximately 367 Americans lost their lives. Of those deads, approximately 165 American casualties, or 45% (official Dept of Defense estimate), were due to "friendly fire". Of all Allied deaths during the Gulf campaign approximately 51% (UN estimate) were due to friendly fire."

Here's a link to the story Arnie mentioned Trooper who saved friend in face of friendly fire awarded George Cross (It was the George Cross rather than the Victoria Cross because the Victoria Cross is only awarded where it's the enemy who are trying to kill you.)