This solemn week marking the 25th anniversary of the terrorist attacks on New York, Washington, D.C., and Pennsylvania, reminded us of the loss of thousands of Americans, and citizens of other countries. Thoreau’s silent arsenal of time may have caused many to forget that the second highest single day of deaths by violence in our nation’s history changed much of our world.The 2,977 killed on September 11 is surpassed only by more than 3,000 killed at the Battle of Antietam on September 17, 1862. Americans living through the Civil War knew there would be more days of Union and Confederate…