Sure, it is possible and I get the picture, but fires are notoriously undisciplined. They wouldn't maintain ranks for long. A city firestorm like Dresden or Tokyo would be unlikely. Just one factor: wind direction and intensity changes constantly and isn't normally uniform to begin with on that scale.
Just one factor: wind direction and intensity changes constantly and isn't normally uniform to begin with on that scale.Good point.
But the forest arsonists could just move over a state or two, and repeat the linear attack every few days until much of the west was burning.
Especially upwind of cities and towns. I think another "Denver fire" could be ignited every day, one arsonist could set ten fires on a line 50 miles long upwind of a city in two hours.
What's to stop terrorists from doing it, other than "hoping for the best"?