It takes three days on the open sea to journey from the Marshall Islands capital to Enewetak Atoll. You can’t see the atoll until you’re just miles away as it’s only feet above sea level. As you get closer, the sun fades behind clouds and the islands are shrouded in mist. Beaches are fringed not by coconut palms but Australian pines, trees praised for soaking up salt-spray and airborne radionuclides.