War has never been sacred.
Since ancient times, war has been the culmination of blood, killing, and violence, a bloodthirsty entity refined from all madness. Victors impose all manners of atrocities on the vanquished without fear of punishment, and many officers not only "lead by example" but also encourage their soldiers to commit various war crimes. This serves to make accomplices of the soldiers, to boost their morale and passion for fighting, and to intimidate the population of occupied areas into submission—killing several birds with one stone.
Thus, since the inception of war, the abuse, slaughter, and plunder of civilians and prisoners have never ceased.
—If there were no war, these atrocities would not exist!
The pacifists can thus criticize.
But the world is not populated solely by pacifists; otherwise, war would not continually exist, and war crimes would have been eradicated long ago.