FILE - In this Saturday, June 22, file photo, people attend the christening ceremony for the future USS Daniel Inouye at the shipbuilder Bath Iron Works in Bath, Maine. The return of shipbuilders after a nine-week strike, which officially ended Aug. 23, 2020, is going smoothly at Bath Iron Works and the union and company already have begun meeting to get back on track. (AP Photo/David Sharp)

In this Wednesday, Aug. 29, 2018 file photo, welder Neal Larsen works on the hull a Zumwalt-class destroyer being built in the shipyard at Bath Iron Works in Bath, Maine. The return of shipbuilders after a nine-week strike, which officially ended Aug. 23, 2020, is going smoothly at Bath Iron Works and the union and company already have begun meeting to get back on track. (AP Photo/Robert F. Bukaty)

In this Wednesday, Aug. 29, 2018 file photo, workers walk by the Advanced Gun System, covered in shrink wrap, alongside a Zumwalt-class destroyer being built in the shipyard at Bath Iron Works in Bath, Maine. The return of shipbuilders after a nine-week strike, which officially ended Aug. 23, 2020, is going smoothly at Bath Iron Works and the union and company already have begun meeting to get back on track. (AP Photo/Robert F. Bukaty)