Technology has put powerful computers in billions of pockets, but an invention much more mundane than the smartphone — the shipping container: a rectangular steel box — also has changed the world. Because of it, two of today’s preoccupations — infrastructure and globalization — are connected by a chain of events that began more than 60 years ago and today runs through Congress and to the wharves of the booming port in Charleston, S.C. In 1934, Malcolm McLean, a North Carolina high school graduate struggling in the Depression, spent $120 earned pumping gas to buy a used truck.