"With all due respect, that's a bunch of malarkey," he told Ryan.
He did what Democrats wished Obama had done last week with Romney: Call out the opponent when you think he's being untruthful.
Biden also told Ryan: "This is a bunch of stuff," referring to the congressman's criticism of Obama's treatment of Israeli Prime Minister Benjamin Netanyahu.
Shuster, the University of Pittsburgh professor, liked the phrase, but thought Biden really wanted to say something, er, stronger.
NOT HOLDING HIS AGE AGAINST HIM:
At 69, Biden was debating a man 27 years his junior. That was not lost on many in the Twitterverse, who sent various tweets referring to Ryan's tender age of 42.
But nowhere was Biden's consciousness of the age gap clearer than when Ryan mentioned President John F. Kennedy as an example of a president who made certain cuts before.
"Oh, now you're Jack Kennedy!" Biden quipped — perhaps eager to channel Sen. Lloyd Bentsen and his famous "You're no Jack Kennedy" quip to then opponent Dan Quayle.
"I knew that was coming because of the age difference," says Shuster. "I even told my students in class today to expect it."
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