A man cannot have only his head up to the sky at all times in a trench or a fox hole. From different angles, different parts of his body will be visible and radiate it's heat. Not to mention that standing up the whole time is probably not going to happen and the soldiers are probably going to be laying down or sitting down.
So are you trying to argue that foxholes and trenches are going to be too shallow or too deep? Seems like you are cherry picking the problems from both, but how can a foxhole be at the same time too shallow and too deep all at the same time?
If the foxhole is too short, you dig deeper, or just lay in it prone.
If it's too deep, use a periscope like they did in WWI, that also handily eliminates all thermal heat from scanners.
Standing up not possible at all time? Please let me know which military unit does not make sure there are sentries on duty at all time when they are deployed into combat? True no one person can keep watch all the time, but why would he? Even a single missile team has two members, take turns.
Either way, trenches or foxholes would get bombed and arty'd out of the earth so that's a null point.
Oh please, we are not talking about WWI era front-long trenches. Good luck finding a few two men teams scattered on the battlefield to call arty and air strikes on.
And with modern innovations like thermal shrouds and decoys, even if you had total control of the air and had UAVs as top cover, you are going to struggle to find tiny targets like that.
And Israel suffers casualties on the premise of deception of Hezbollah.
Hate to break it to you, but the premise of deception is what all sides strive for in war.
It's not some sport of honor duel ffs. Like the Israelis gave Iraq or Syria fair warning that they were going to bomb them beforehand.
There's a picture or two of a dump truck in Gaza where it looks like a dump truck, but it has 122 mm tubes below the dumper-thing, so that when it raises the dumper-thing to dump it's payload, it's rocket tubes reveal and allows it to fire rockets.
How does dump trucks come into it when we are talking about ATGM teams v MBTs in a near peer country v country context? You think your tank commanders are not going to find it mildly puzzling if a fleet of dump trucks suddenly appeared on the battlefield?
If anything, your 'example' illustrates my original point that good old fashioned innovative tactics can easily bypass modern sensors.
Very discreet they are, and the only real way to counter such a thing is quarantine apparently! Just more examples of simple deception that can't be reprimanded without the harsh treatment that Israel imposes on the Palestinians.
And now we are getting political. Shall we steer clear of that can of warms before we get hot heads defending and bashing Israeli treatment of the Palestinians?