Caterpillar, the heavy equipment manufacturer, is moving to lay off more than 20,000 workers. These days such mass layoffs are sadly unsurprising, but are they ethical? If Caterpillar is to relegate legions of employees to the care of the public, it may not simply echo Ebenezer Scrooge: “Are there no prisons? Are there no workhouses? Is there no COBRA?” Instead, it must use its considerable political clout to ensure that those programs are robustly funded, hardly a priority either for Caterpillar or its confreres among the Fortune 500. That is, if Caterpillar is to deprive thousands of people of a...