The fire was in a military weapons area, there were unexploded ordinance there making normal fire fighting difficult .... on the other hand it was likely easy to get permission to drop another bomb there

Just because another country does something stupid doesn't make it a good idea. Also, as noted in another comment, the one time this was done in Sweden, it was a fire on a military base.

In the U.S., cultural resource protection is one of the considerations in wildlands firefighting, and a significant number of wildfires in the U.S. west occur within designated Wilderness areas where minimum impact suppression efforts are required by law. This means, e.g., you can't run a bulldozer through to cut a fireline in Wilderness, and in some cases can't even drop slurry because it might cause permanent staining on rock outcrops, damaging a natural resource. Dropping weapons-grade bombs is going to be a non-starter, as it should be.