He wouldn’t allow signs at his rally for “security” reasons but the Secret Service said they do not have a problem with signs:

NOT ALL COUNTRIES guarantee their citizens the right to virtually unbridled freedom of speech. The United States does. Would someone please tell the campaign of Sen. Barack Obama? And the dozing guardians of liberty at the University of Mary Washington?
Mr. Obama, the Democratic nominee for president, is scheduled to speak at a rally at the university today. The public is invited to this forum, on property it, the public, owns. However, signs and banners will not be allowed, according to the organizers and compliant campus officials. Suddenly, UMW is a First Amendment-Free, or at least a First Amendment-Crippled, Zone, subject to the self-serving preferences of politicos. Why does an Obama rally–or a McCain rally or a Nader rally–justify taking a little off the top of Americans’ most fundamental rights?

What a contrast with a McCain-Palin rally where home-made signs are rampant. It tells you something about how each candidate views the rights of the people who come and see them.
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