It is certainly not the intention of the government or of industry in general to eliminate intruders. That's why they post warnings
If I put up an electrified fence around my house, with proper warnings posted, how is that any different from what governments do? I'm only protecting the public from the pitfall traps dug in my yard, after all.

I seem to recall some rather famous trials took place in Nuremburg.
Yes, with the loser's on trial, as I said. I don't recall reading of any trials condemning the Russians for the depravities inflicted upon civilians by their soldiers, or the enslavement of prisoners of war. But then, they were on the winning side, weren't they?

Sometimes it might be difficult to draw that line between a legitimate act of war and a war crime ... on which side did Blitzkrieg fall?
Blitzkrieg was a type of warfare, utilizing the speed and maneuverability of armored units. It has nothing to do with war crimes. Allied forces used the same techniques, once they saw how effective they were.

With very few exceptions, actions performed by the winners in the war are not generally treated as war crimes.

Who in their right minds advocates detonating bombs at random without regard to the consequences?
Why do you assume there would be no regard for the consequences? If you assume that the bombs will NOT be found before they are placed at their targets, and you can only prevent that by randomly broadcasting radio waves that MAY detonate some of the bombs, isn't it likely that any damage, and casualties, will be far less than if the terrorists hit their planned target? Plus you are more likely to kill the bomb maker. Another plus.

Personally, I'll go with shooting the SOB while he's still making the bomb. Or is that too soon? After all, manufacturing a bomb is not an immediate threat, is it?
And that, Thorne, as you well know, is murder
Is it? Isn't making a bomb a terrorist act? Basically, an act of war? So killing the terrorist is also an act of war, is it not? Especially if the shooting is done by the police or the military.