Ecologically, wildfire is generally considered a part of the climate. The pine forests of arizona burned every 3 to 7 years with light underburns that maintained the species adapted to it prior to grazing and putting the fires out. Putting out every fire, even the light ones, has allowed the fuels to accumulate so that when it does burn, it burns with much higher intensity than it did in prehistory, so it kills a lot of the overstory trees.
Native americans didn't scrape a 20 foot circle around their campfires, so escapes were common. But most fires were from lightning, as if a snag got hit, it would smolder until the weather got hot and dry enough and there was fuel to carry the fire.
Wildland fire is often due to carelessness, and even when it is deliberate arson, it takes the right weather to do damage. In the past, thinning and harvesting made a fuel mosaic to slow fires, but since harvesting has been stopped in most areas, the fires run unimpeded. And building houses in the middle of huge fuelbeds is just plain stupid and something we all pay for with our insurance premiums.
Oddly enough, much of wildland arson is by ex firefighters. But when the conditions are such that a fire can run to hundreds of thousands of acres, the actual ignition was statistically likely to happen even if it was not deliberate. Most areas have ignition fire responses almost daily, but they only escape control when the weather is right, normally. But we love to have scapegoats, so when a dumbass arsonist hits the weather right, he becomes the lucky winner of a lifetime in jail.
Even if there wasn't the current Climate Turbulence thing going on, much of the west is set up for gigantic fires anyway due to fuel accumulation. It gets hot and dry every summer anyway, as we have a mediterranean climate, so the actual limiting factor is fuel availability. It also means that if there are punk arsonists, the results of their work will cause more damage than in the past.
In recent years, about half of the budget of the Forest Service and the junior varsity of land management agencies, the BLM, came for treating fuels, particularly in the wildland/urban interface, but that funding has evaporated with the wars, so the fires like arizona is having will be commonplace in the future. Sad, but true. And will happen even if arson was reduced to zero.