Del Toro served in the United States Navy as a Surface Warfare Officer for 22 years, retiring with the rank of commander.

[6] After retiring from the Navy, Del Toro founded SBG Technology Solutions, Inc., a program management and engineering firm that primarily works with government clients.

[16] Del Toro's nomination received praise from Armed Services Committee Chairman Jack Reed, who described the nominee as an "excellent selection.

"[17] During a July 13 committee confirmation hearing before the Senate Armed Services Committee, Del Toro received "mostly friendly" questions from senators, although some Republicans expressed concerns about the size and perceived inadequacy of President Biden's FY2022 defense budget and America's commitment and ability to defend Taiwan amidst rising US–China tensions and a recent American failure to defend the island nation in a military simulation.

[24] In April 2023, the Military Religious Freedom Foundation shared a video of a town hall meeting where Del Toro made comments which some observers perceived as homophobic.

"[25] On September 5, 2024 it was reported that Secretary Del Toro violated the Hatch Act for statements voicing support for President Joe Biden during a work trip to the United Kingdom in January, according to the U.S. Office of Special Counsel.