The United States actually needs to have a salutary crisis in Illinois. It will be salutary because it will be a cautionary example for other states if Illinois suffers, without offloading pain on taxpayers elsewhere, the severe consequences of decades of ruinous choices. And Puerto Rico’s troubles will benefit America if the bond market, sobered by a demonstration that government bonds can be risky, becomes a restraint on state legislatures by raising the cost of borrowing where the legislatures are most irresponsible.