Mikhail Kalashnikov, small arms designer of the infamous AK-47 assault rifle, died just before Christmas, at age 94. And it's just now come to light that the honorary Russian general repented for his contribution to modern warfare in a letter sent to Patriarch Kirill of the Russian Orthodox Church in May 2012.

Per BBC News' translation of Kalashnikov's letter published by Russian newspaper Izvestia:

The pain in my soul is unbearable. I keep asking myself the same unsolvable question: If my assault rifle took people's lives, it means that I, Mikhail Kalashnikov . . . son of a farmer and Orthodox Christian, am responsible for people's deaths.

The letter was typed on Kalashnikov's home stationery.

Like the man himself, obituaries of Kalashnikov agonized the AK-47s contribution to the death tolls of so much military conflict and civil unrest throughout the past six decades. As early as 1989, Kalashnikov lamented the "misuse" of his most famous rifle design, according to Smithsonian historian Ed Ezell. Likewise, a spokesman for the Russian Patriarch commented to Izvestia, "[Kalashnikov] designed this rifle to defend his country, not so terrorists could use it in Saudi Arabia."

Since the Soviet Union's initial mass-production of the rifle in 1949, more than 100 million AK-47s have been sold worldwide.

Throughout the Soviet era, Kalashnikov was a much decorated figure in both civil and military regard. Honored into the twenty-first century, even, as the world now learns Kalashnikov's own doubts and dismay regarding his invention's role in violence of various scale—local, civil, international—long astray from the Soviet Union's Cold War defense against the West.

The longer I live, the more this question drills itself into my brain. And the more I wonder why the Lord allowed man to have the devilish desires of envy, greed and aggression.

In the U.S., most states permit sale and purchase of semi-automatic AK-47s.