It was a brief episode in what has been a long and gruelling campaign, but it spoke volumes about an issue that has been percolating since this election began. On October 10, in Lakeview Minneapolis, at a rather raucous town meeting hosted by Republican presidential nominee John McCain, one of his supporters, an older woman named Gayle Quinnell, was given the microphone to speak. Haltingly, she said, "I don't trust Obama. I've read about him, and he's an Arab." McCain, clearly uncomfortable with the situation, grabbed the microphone from her and said, "No, ma'am, no ma'am. He's a decent family man, citizen, that I just happen to have disagreements with on fundamental issues. That's what this campaign is about. He's not. Thank you." It was an unsettling moment, for several reasons, For almost two years now, emails and pamphlets have been widely circulated, saying not just that Barack Obama is a Muslim but, more ominously, charging that he is a "secret Muslim" and a "Manchurian candidate" planted in our midst to disrupt out democracy. As bizarre as it all sounds, questions have been raised about Obama's place of birth, his beliefs, his associations - all suggesting that we don't know who he is, what he stands for, or what he will do to America. These fantastic charges were echoed on talk radio and fuelled by extremist preachers. As a result, they acquired some currency. In ways subtle and not so subtle, Obama's opponents, first in the Democratic primary, and now even more harshly in the general election, have fed this slanderous effort. In the beginning, it was "He's not like us," or "We don't know who he is," or "He doesn't believe in the same America the rest of us believe in." By now, it's become "He's a liar," "He pals around with terrorists" or, as Rush Limbaugh continues to say, "He's really an Arab." As late as this week, the Virginia Republican Party sent out a mass mailing featuring a cropped photo of Obama's eyes, with the logo: "America must look evil in the eye and never flinch;" while North Carolina's Republican Party made automated phone calls to people's home linking the Democrat to terrorists. And a prominent Washington-based conservative newspaper featured an article with the headline The Jihadist Vote, making allegations about "Islamists seeking to destroy Western civilisation from within," utilising the Obama campaign as their vehicle. Repeated often enough, even fantasies can find fertile ground amidst economic insecurity and "fear of the other" (a nicer way of describing racism and Islamophobia) and be believed. This is what found expression in the words of Gayle Quinnell. Now, as unsettling as this was, I was also troubled by Senator McCain's response. While he was, at first, widely credited by the mainstream media for defending his opponent, I found disturbing the implication conveyed by his awkward reply, that being an "Arab" and a "decent family man" were somehow mutually exclusive categories. And so my office issued a rebuke, and I posted a piece on Huffington Post, one of the US's most prominent blog sites, entitled "John McCain: I am an Arab and a Decent Man." In it, I wrote: "Enough is enough...while we are pleased to see that [McCain] is trying to dispel rumours about Senator Obama, we feel the need to point out that Arab Americans are also decent men and women with full rights and citizenship as enumerated under the constitution. Arab Americans are part of the great melting pot that is this country's strength. We raise our sons and daughters to be model citizens of this nation. We serve this country with honour. The suggestion that any ethnic group is treacherous and anti-American is unacceptable, dangerous, and unbecoming." The response I received was overwhelming and extraordinarily positive. Hundreds and hundreds wrote comments and/or emails, among them were these statements: "    "These kinds of comments defame not only Arab American, or African Americans, but every American." "    "We are all Arab Americans. Since Friday, I have become one." "    "As an American of Japanese ancestry, I know fully well the impact of hysterical mob mentality." "    "That hurt me as an American." Equally noteworthy was the slow but steady response by media commentators on CNN and MSNBC, as well as a delightful sketch on Comedy Central's  Daily Show with John Stewart - all of which chided Senator McCain for failing to recognise that "Arab" should not be used as mud to sling at an opponent. The collective response was heartening, and reinforced my belief in the fundamental goodness of my fellow citizens. This election has been long, and it has been difficult. It has exposed raw nerves at the core of the American psyche: race, and fear of Arabs and Muslims (long a problem, but exacerbated by the horrific terror of 9/11) are problems we must now address. As long as they remain unaddressed, they can be the fodder of incitement, used to prey off of fear and insecurity. No doubt, a dangerous situation. But there is a lesson to be learned from the Gayle Quinnell and McCain episode, and that is: If left unchecked, the hatred will grow, but when challenged, it can be defeated. The writer is the president of the Arab American Institute, Washington DC