But you can't use it for brave Molotov cocktails. 
It's fun to put in a spray bottle and spray it on fires though
That's the thing. You have to pressurize diesel and atomize it as you release it into the air to get a nice flame thrower effect.
I once adapted an air compressor hose to a long thin tube and attached an oil can to it, which operated like a venturi powered siphon as the air sprayed. I used it like a WD40 spray can from HELL when I needed to hit some of the areas out of reach when dealing with bus maintenance.
One day I had the "bright idea" to light the spray on fire. Then I tried other things besides oil to spray. A can of diesel worked great.
I am still paying for foolishly expanding my carbon footprint, needlessly.