I'm being a bit unfair in that I'm counting hesco as a kind of trench warfare, but you're right in that that doesn't exactly apply on 'patrol'

Still, I believe earthen barriers are still used to solidify the 'frontlines' if you squint a bit

Afaik the Iraq Iran war was still doing straight up trench warfare (at points) and the Syrian civil war + Afghan theater were using caves (in some areas). Same with Korea and Vietnam.

Then again you're right in that I don't think sudan etc have used trench warfare (in the first civil war, apparently the second one has on a post edit search: https://www.bbc.com/news/world-africa-65962771 )

You're completely right on the second Iraq war, I don't see any sources for trenches, minus hesco.

I think what I comes down to is trench warfare is popular for the same reason earthworks are popular in civil engineering. Cheap, locally sourced, and effective in its purpose.

> the Iraq Iran war was still doing straight up trench warfare (at points) and the Syrian civil war + Afghan theater were using caves (in some areas)Same with Korea and Vietnam

Static versus combined arms. The U.S. military is deadly not only because it is big, but also because it practically invented and then mastered modern combined-arms warfare. (It’s why we put so much emphasis on air superiority over e.g. armour.)

Are you defining trench warfare as "has a trench"? Because I meant the system of long lines under fire for weeks/months and high-attrition infantry attacks across the narrow no man's land to take slivers of territory.