SAN JUAN, Puerto Rico -- In the aftermath of Hurricane Maria, U.S. Army Maj. Alexander Walker has served as a human bridge linking the task force charged with restoring power in Puerto Rico to citizens greatly in need of electricity. As an engineer officer since 2006, Walker is accustomed to construction and demolition tasks under combat conditions, building structures, and designing civil works. In his newer role as a community liaison, what Walker builds now are relationships.