WILMINGTON: In a public ceremony delayed two years by the pandemic, President Joe Biden on Saturday commissioned the USS Delaware, a nuclear attack submarine, saying it would enhance national security, though he made no reference to the global turmoil from Russia's invasion of Ukraine.

'As the commander in chief, I believe it is our sacred obligation as a nation to prepare and equip those troops that we send into harm's way and to care for them and their families when they return home,'' he told a crowd of invited guests and dignitaries assembled on a sunny but chilly spring day on a restricted part of the dock in Wilmington.