President Donald Trump’s $1 trillion plan to rebuild America’s infrastructure may be unprecedented in size and ambition, but it mimics a controversial scheme championed by Vice President Mike Pence when he was the governor of Indiana. That’s why Pence is the public face of the Trump initiative, and executives from financial firms that helped privatize Indiana’s toll road are in the White House, busily sculpting Trump’s national plan. Pence and his allies like to boast about how Indiana sold control of major roads to private firms, claiming the move prompted corporations to invest money in infrastructure that would otherwise have...