Inspired by the several threads going around about the potential for the US to develop a substantial inter-city rail network, I thought I'd try to create a semi-plausible timeline in which that happens:
Our story begins on June 17, 1972. Security guard Frank Wills is patrolling the Watergate Complex when he notices tape covering the latch on one of the doors. He removes the tape and continues on his rounds. When he returns 30 minutes later, he doesn't check to see if the tape has been replaced, as he has no reason to believe that there is anyone else in the building. The next day, one of the staffers at the Democratic National Committee thinks that the papers in their office have been moved overnight, but Wills reports that he saw nothing suspicious.
One year and four months later, President Richard Nixon has weathered the resignation of Vice President Agnew and is riding high in the polls as Vietnam finally seems to be settling into a stable peace, but the Arab oil embargo threatens another recession. Nixon huddles with his advisors and comes up with a plan that will cut the United States' dependency on foreign oil. Deputy Treasury Secretary William E. Simon will serve as the nation's first Secretary of Energy, responsible for overseeing a system of gasoline rationing in the short term and overseeing the construction of new nuclear power plants to replace existing oil-fired plants. At the same time, Nixon reluctantly admits that the Amtrak system he had hoped to use for a quiet sunset of passenger rail service will be necessary to reduce the need for automotive transport. Congress authorizes Amtrak to acquire the assets of the near-bankrupt Penn Central and Eerie Lackawanna Railways, instantly creating a publicly-owned rail network stretching from Boston to Chicago and south to St. Louis. In addition to freight and the legacy inter-city passenger rail lines, the network allows local and state governments to set up commuter lines using its rights-of-way. These lines connect inflation-weary suburbanites to the new Metro systems being built in Washington DC and Baltimore, as well as existing networks in New York, Chicago, Boston, Philadelphia, and Cleveland. The Energy Department begins electrifying the tracks to create an improved power grid connecting proposed nuclear plants in the northeast to major urban centers.