"The Civil Rights Act of 1964 was the single most important piece of legislation passed by Congress in American history. This one law so dramatically altered American society that, looking back, it seems preordained--as Everett Dirksen, the GOP leader in the Senate and a key supporter of the bill, said, "no force is more powerful than an idea whose time has come." But there was nothing predestined about the victory: a phalanx of powerful senators,...