Don't care about whatever the other argument is, but...
You God damned fucking RETARD.
PoWs are a political tool you retards. It's the golden fucking rule. Not taking prisoners might be a good strategy if you're some 1800s European country trying to get some of them there cheap raw materials for pennies by letting your impoverished/dregs of society fuck the natives to give you a semi-loyal and cheap workforce in said imperial colony, but unless your goals are imperialism or genocide (or both), you have to be a fucking retard to kill prisoners of war. The end goal of most military conflicts is not complete annihilation of hostile troops, that's why usually only officers are prosecuted following a war. As counter-intuitive as it might seem, death troops (don't remember the proper term but I know there is one) are a real thing, and are a real consideration in military strategy, as is the threat of rebellion from the local populace. Men start doing some real scary, real screwy shit when they know the enemy doesn't take prisoners and that they're a dead man, and CIVILIZED Europeans have understood this for the last 2000+ years. Just from a logistical standpoint, not taking PoWs is the equivalent of shooting your own forces in the back because:
A) When forced to fight to the last man, soldiers have been shown time and time again to be much more resolved/efficient in killing your men since the fear of death is no longer a factor (this is QUANTIFIABLE with friendly casualties SPIKING in conflicts where prisoners were not taken).
B) As I said above, the golden rule applies and your enemy will not hesitate in killing your potential future assets in retaliation.
C) The slippery slope is real, and the moment killing surrendered soldiers is on the table is the moment using chemical weapons and other shit on civilian areas is also an option.
"War crimes" are not excuses for larger countries to rain shit on smaller countries, holy fuck. War crimes are gentlemen agreements established back during WWI when some countries lost as much as 8% (or even more in some cases) of their working-age male population in a time when most countries were still industrializing. In fact the numbers are skewed because those 8% figures don't adjust for men in that age group, but account for ALL men in said countries regardless of age, and that's just deaths, that doesn't include those permanently crippled. You still have to go home after a war, and crippled/dead men are a drain on society in most cases, not a benefit. Those are men potentially no longer working, fucking and having babies, etc. 99% of armed conflicts are not fucking wars of annihilation/genocide, they're wars with specific objectives in mind that the higher ups are trying to achieve whether it be resources, territory, whittling down a rival, etc. At the end of the day, you aren't just losing numbers in a conflict, you are losing the fucking lifeblood of your nation that keeps it from being subverted by women and cucks you fucking faggots. Go watch that Armenian
propaganda video documentary team on jewtube. Read the fucking subtitles. The soldiers are the local men. In the video you had a principal, geography teacher, and town mayor all acting as part of the standing army, and that behavior likely spawned BECAUSE of Turks and Azeris being fucking roaches that don't honor gentlemen's agreements like recognizing war crimes for what they are. That video of 60 dead roaches wouldn't have happened if the Azeris had played by the rules since the civilians wouldn't have gotten involved in the conflict.