Zen flowered during the Tang dynasty in China, at a time when central control was breaking down and the many parts of the country were overrun by warlords and rebellions. Think of Syria with knives and swords instead of barrel bombs, drones, and automatic weapons. At one time during this period about 1/3 of the deaths were caused by the direct or indirect results of war, such as disease and starvation. Yet instead of taking up arms, our Zen ancestors took to the mountains to practice hard. They could see around them the result of confusion of mind. It wasn’t pretty. It still isn’t pretty. They realized that the real enemy is exactly this confusion. Not confusion because you have the wrong opinion. But confusion because you have an opinion, and you’re sticking to it, and you’ll mow over anyone who stands in your way.
So that’s where Zen practice was formed: in the crucible of tremendous suffering, as a way to end suffering, not just your own suffering, but the suffering of all beings. We practice to clarify our minds so that our actions alleviate suffering instead of causing more suffering.