Those of us who live in California’s wildfire areas (most of the hilly areas of the state) know there is quite a bit of defensive measures that can be taken.
There should be a defensive perimeter of 20 – 50 feet around all structures with all possible fuel removed. Roofs should be cleared of debris and leaves or pine needles, and overhanging trees should be cut back. And roofs should be made of falme resistant material, not cedar shake.
There are also extensive firebreaks of 20 feet cut through most of the open space around here. Our local fire department actually does extensive reviews on the ground and in the air to make sure people have cut weeds and have cleared debris.
There used to be controlled burns done around here until about 15 years ago when one got out of control and ended up burning about 500 acres of open space. The wind changed in mid afternoon and started burning in the wrong direction. Even with fire equipment in place, it took a while to get it back in control. It’s not done in our county anymore.
As @john65pennington says, though, fires will happen, and will destroy large areas. We had dry lightning here Friday night that started five fires in less than an hour on Mt Diablo. Luckily, the fire department had anticipated it and was ready.