Did anyone notice the implicit message that Arabs are not decent family men?

Here's the link to the San Francisco Chronicle story: 

On Friday, McCain found himself in a tricky balancing act - booed
by supporters at a Minnesota rally when he urged them to "be
respectful" of the Illinois senator, even challenging one woman who
said she didn't trust Obama because "he's an Arab."

"No, ma'am," McCain responded. "He's a decent family man, citizen;
I just happen to have disagreements with (him) on fundamental issues."

So, I get that McCain wants to counter the idea that Obama is an Arab; what I don't get is the implication that Arabs aren't decent family men! One day, a member of the Arab-American community, a son or daughter of immigrants, will run for elected office, and this kind of discrimination will be unacceptable.