Re: liquid bombs
I agree with your larger point.
But the liquid bomb thing is real. Surprisingly.
Example: the standard issue USA police/FBI demolition explosive is 2 clear liquids. Visually indistinguishable from water and with little to no scent, easily masked. Separately, inert; mixed, they are about as powerful as dynamite.
You can see an example for yourself if you dig up the Mythbusters episode where they blow up a cement mixer truck in a quarry. Their police buddy is shown prepping the explosive.