If Ali dared to repeat her slander that Muslims all belong to the same "nihilistic cult of death," she would repel far more listeners than she would persuade. Anytime a speaker with a controversial record comes to campus, it's a gala opportunity to remind the audience of what they have to account for.
Why silence speakers when you can denounce or even shame them? When President Barack Obama spoke at Notre Dame in 2009, anti-abortion advocates flocked to condemn his policies. A plane pulled a banner picturing the remains of a fetus with the message: "10 Week Abortion."
At Sen. Rick Santorum's 2003 appearance at St. Joseph's University, some students attached rainbow-colored tassels to their mortarboards in a silent show of support for gay rights. At the UC Berkeley law school ceremony in 2011, protesters handed out orange ribbons to express outrage at former Bush administration official John Yoo's complicity in torture.
When former New York Mayor Rudy Giuliani spoke to graduating students at Syracuse in 2002, some waved their wallets -- reminding him of Amadou Diallo, an unarmed Bronx man killed by a hail of police bullets after he reached into his jacket and pulled out a billfold.
It wouldn't be hard to find provocative ways to disavow some of this year's invitees while allowing them to say their piece. Birgeneau's critics could splatter their gowns with yellow paint to match the pepper spray used on seated demonstrators.
Rice's detractors might sport atomic symbols to evoke the weapons of mass destruction that Iraq didn't have. Islamic students and parents could have greeted Ali with signs saying, "This is what a peace-loving Muslim looks like."
The best response to allegedly villainous speakers is not to turn them into martyrs by denying them a forum. The best response is to let them speak and make them wish they hadn't.