Sooner or later, time will run out in the pursuit of Nazi-era war criminals as they are overtaken by death after decades of undeserved freedom. This makes it all the more noteworthy that an 88-year-old German man was charged this week with the murder of 25 people in a wartime massacre in the French village of Oradour-sur-Glane. The case, prosecuted by German authorities, is a reminder of a haunting period of history that must be kept in mind as fresh acts of genocide bedevil the world. In the French massacre, SS troops shot and burned to death 642 people.

Anyone tempted to relegate such slaughter to the deep past needs to know of a current development that hardly seems unrelated — the surge in e-book readership of “Mein Kampf,” Hitler’s blueprint for the mass extermination of European Jews. The e-book version of the work was reported this week to be the top seller on the Amazon political psychology list. The phenomenon shows that, more than ever, people need to know of the genocide rooted in Hitler’s ideas, and those facts need to be detailed in trials.

Since 2001, there have been more than 100 successful legal actions against Nazi war criminals, according to the Simon Wiesenthal Center, the Nazi hunting organization. Dozens more have been prepared, but center workers say other nations are not as committed as Germany to following through on this obligation of justice. (In France, the government has been aggressive in attempting to block crowd-baiting appearances by Dieudonné M’bala M’bala, a controversial comedian who has been convicted after using anti-Semitic hate speech in his routine.)

The Nazi hunt must continue, particularly since life expectancy is rising, according to Efraim Zuroff, director of the Wiesenthal Center’s Israel office. “I’m one Jew who prays for good health for these fugitives,” said Dr. Zuroff.