As a recent controversy in California makes clear, protests targeting radical Islam are a double-edged sword and must be carried out with discipline. Done right, they expose Islamists and their work to much-needed public scrutiny; done wrong, they play into the hands of Islamists eager to silence all critics by characterizing Muslims as victims of vast prejudice and aggression.

On February 13, hundreds gathered on the lawn of the Yorba Linda Community Center to protest a fundraiser for ICNA Relief, a social services arm of the Islamic Circle of North America, which has ties to jihadists overseas. Not surprisingly, two of the most extreme Muslim clerics in the country, Siraj Wahhaj and Amir-Abdel Malik-Ali, were invited to speak at ICNA's event.

Based on the flags and songs, the Orange County Register described the protest as having "the atmosphere of a July 4 picnic." Local politicians and two congressmen addressed the audience (video here). Their remarks were firm but largely tasteful, though Councilwoman Deborah Pauly (video here) could have made her words more difficult to take out of context if she had directly cited ICNA and the imams when she labeled "what's going on over there" as "pure, unadulterated evil," before explaining that U.S. soldiers know how to dispose of "terrorists."

But Pauly was not the problem. Accounts indicate that a smaller mass of demonstrators, separate from the main crowd and continuing long after the official rally had ended, assembled near the facility's entrance and verbally harassed Muslims, including families. On March 2, CAIR-Los Angeles released a video documenting the crude shouts of the splinter group: "Go back home!" "You beat your women and you rape your children!" "Go have sex with a nine-year-old and marry her!" True to form, CAIR heavily edited its video by interspersing clips of lawmakers at the earlier rally with later footage of the second group's poor behavior, thus painting everyone with the same brush. Dishonest, but effective.

Unfortunately this is not the only time that American demonstrators have gone overboard and handed Islamists a propaganda victory. For example, a protester at the Islamic Center of Temecula Valley in California reportedly called Muslims "pedophiles" and cursed at them last July. In August, "Jesus hates Muslims" was the chant as Christians descended on Masjid An-Noor in Connecticut. Talk about a recipe for losing the public relations war with radical Islam.

Some advice for protesters: First, focus on the specific histories of Islamists associated with a given event or project; never smear ordinary Muslims in attendance by accusing them of the worst practices seen in the Islamic world. Second, record your peaceful rally, as the video may prove useful when allegations fly. Third, quickly distance yourself from obnoxious interlopers who might piggyback on your demonstration; do not sit around hoping that CAIR failed to notice them, only to be caught flatfooted once the Islamists inevitably go on offense.

Remember: to advance their agenda, CAIR and its allies need film of boors yelling insults at Muslims. Those lacking sufficient self-control to distinguish between true radicals and everyday Muslims arriving at a dinner or going to a mosque would do us all a favor by staying home.