Sub Visit Defense Secretary Dr. Mark T. Esper visits the USS Boise attack submarine in Norfolk, Va., Sept. 25, 2019. Esper is with the commander of submarine forces, Vice Adm. Charles A. Richard. SHARE IMAGE: Download Image: Full Size (4.81 MB) Tags: defense secretary, esper Photo By: Lisa Ferdinando, DOD VIRIN: 190925-D-BN624-0279.JPG Photo Gallery