When Kentucky Republican Mitch McConnell interned in the Senate 50 years ago, he watched his Republican boss work with a Democratic president. The issue was civil rights.
Now that he has his dream job as Senate majority leader, he's doing the same thing. The issue now is trade.
In some ways, McConnell's work alongside President Barack Obama is more surprising than his old boss Sen. John Sherman Cooper's cooperation with President Lyndon B. Johnson. The two parties weren't nearly as polarized then as today.