Third, Western leaders need to adopt a different attitude toward the Russian leader. Putin runs an enormously corrupt, authoritarian regime that has as its main goal staying in power at any cost. He has caused the deaths of thousands of people, destabilized his neighbors, supported murderous like-minded tyrants elsewhere around the globe, and repeatedly violated the human rights of his own people. He may be popular among Russians these days, but that should not deter the West from pursuing a principled policy.

Placing Putin himself on the visa ban and asset freeze list would be a huge step, equivalent to a declaration of political war. But if the downing of MH17 doesn’t get people to start thinking along such lines, how many more innocent victims will it take?

Those of us who have been calling for tough sanctions for months have been warning that things could spin out of control and that, undeterred, Putin might threaten other countries in the region and beyond. The tragedy of MH17 should be a wake-up call to Western leaders to stop dragging their feet and to take decisive action now. They should stop treating Putin as a normal leader and instead treat him as the international pariah that he is.