President Donald Trump is directing his administration to investigate Joe Biden’s actions as president, alleging aides masked his predecessor’s “cognitive decline” and raising questions about his use of the autopen to sign pardons and other documents.

At a fateful event last summer, Barack Obama, George Clooney, and others were stunned by Biden’s weakness and confusion. Why did he and his advisers decide to conceal his condition from the public and campaign for reëlection?

The president alleged that his predecessor’s aides hid evidence of what he called Biden’s “serious cognitive decline.”