Counteraction to Kali

In this age of Kali the propensity for mercy is almost nil. Consequently
there is always fighting and wars between men and nations. Men do not
understand that because they unrestrictedly kill so many animals, they also
must be slaughtered like animals in big wars. This is very much evident in
the Western countries. In the West, slaughterhouses are maintained without
restriction, and therefore every fifth or tenth year there is a big war in
which countless people are slaughtered even more cruelly than the animals.
Sometimes during war, soldiers keep their enemies in concentration camps and
kill them in very cruel ways. These are reactions brought about by
unrestricted animal-killing in the slaughterhouse and by hunters in the
forest. Proud, demoniac persons do not know the laws of nature, or the laws
of God. Consequently, they unrestrictedly kill poor animals, not caring for
them at all. In the Krsna consciousness movement, animal-killing is
completely prohibited. One is not accepted as a bona fide student in this
movement unless he promises to follow the four regulative principles: no
animal-killing, no intoxication, no illicit sex and no gambling. This Krsna
consciousness movement is the only means by which the sinful activities of
men in this Kali-yuga can be counteracted.

Ref. VedaBase --> SB 4.26.5