Why Destroying Every French Port Didn't Stop the Allies — Who Brought Their Own Harbor Across Sea

In the last week of June 1944, German engineers carried out what a U.S. Army colonel called the most complete and best-planned demolition in history. They turned Cherbourg, the finest deep-water port on the coast, into twenty thousand cubic yards of rubble. It changed nothing. Both sides had spent the war believing the same thing: that no army could be supplied across open beaches, and that whoever held the ports held the campaign. The Germans built their entire coastal defense around it, turning every major harbor into a fortress meant to be wrecked before it fell. And then the Allies did something no one had done before. They built two artificial harbors in secret, each the size of Dover, towed them across the Channel behind the D-Day assault, and bolted them to the seabed off the invasion beaches. This is the story of the Mulberry harbors, the storm that did in three days what four years of German coastal defense could not, and the question the men who were there never settled: whether the Allies ever needed them at all.