A-Bomb Dome is seen near Hiroshima Peace Memorial Park on August 5, 2010 in Hiroshima, Japan,. (Photo by Kiyoshi Ota/Getty Images)

By Daryl G. Kimball

Since the devastating U.S. atomic bombings of Hiroshima and Nagasaki 69 years ago this week, the catastrophic effects of nuclear weapons have motivated ordinary citizens to push their leaders to pursue arms control and disarmament measures to reduce the threat of nuclear weapons use.

For decades, it has been well understood that the direct effects of a large-scale nuclear conflict could result in several hundred million human fatalities, while the indirect effects would be far greater, leading to the loss of billions of lives.

An April 1979 U.S. Arms Control and Disarmament Agency report found that an exchange of U.S. and Soviet nuclear forces involving a total of approximately 18,000 strategic warheads would kill 25-100 million people in both the U.S. and the Soviet…