William S. Knudsen is grey-haired, bulky, ruddy. Walter Philip Reuther is rufous, pint-sized, pale. Messrs. Knudsen and Reuther first knocked their heads together when one worked for General Motors, the other for the C. I. O. autoworkers' union. Frazzled after a tough bout with a union committee in Detroit, G. M.'s Knudsen once glared at Walter Reuther, barked:
"Young man, I wish you were selling used cars for us."
"Used cars!," squawked Mr. Reuther.
"Yes," said Mr. Knudsen, "used cars. Anybody can sell new cars."
Walter Reuther did not take the angry compliment as an...