Jack Teixeira, a former member of the U.S. Air National Guard, has been sentenced to 15 years in prison for leaking sensitive and classified information about the war in Ukraine. This leak shocked both the U.S. government and Ukraine, as the documents contained important military details, including U.S. training of Ukrainian troops and the flow of Western weapons into the country.

In March, Teixeira pleaded guilty to leaking top-secret materials. He admitted to posting several classified...