ALBUQUERQUE, N.M. (AP) — The nation's top nuclear security official is in New Mexico to commemorate the 75th anniversary of the the world's first atomic explosion. The test is both revered for the scientific advancements it helped to usher in and vilified for the moral and diplomatic implications that still linger in its wake. Lisa Gordon-Hagerty, head of the National Nuclear Security Administration, says the Trinity Test in 1945 helped to avert wars and saved untold millions of lives over the years through advancements in nuclear medicine and science. For others, the atomic test in southern New Mexico and subsequent tests elsewhere have left a painful legacy.