The 60% figure is in the ballpark from what I have seen...That certainly is not just "some."
Mosques/Muslim organizations in the US have not been aggressive against the radical Islamist ideologies. Look at the emphasis they put on criticizing Israel. Why can't they do the same for jihadists? The last time I checked Israel isn't plotting to blow up skyscrapers in Dallas or courthouses in Ohio. If anything, Muslim organizations have hindered the anti-terror effort by suddenly becoming civil libertarians. Muslims did not care about civil liberties before the FBI began fighting terror and look at Muslim countries today. Name one which has liberal civil liberties...
What has happened since 9/11 is Muslim organizations and leaders have changed their rhetoric. Some of them, such as ISNA in its magazine, do condemn terror and murder. Some play a double game. Notice that whenever a CAIR spokesman is on television he will say "I condemn all forms of terrorism." Why can't he bring himself to say "I condemn Al-Qaeda."? He is playing to some of his base. He knows many of them sympathize with Al-Qaeda and he can say "I condemn all forms of terrorism" because he wants to mislead non-Muslims and because he can wink and nod at his base, who do not consider Al-Qaeda's actions to be a form of terrorism.
Others, while condemning terrorism, remain hostile to the culture and society they or their parents voluntarily immigrated to. Hamza Yusuf is considered the most influential imam in the US. Read between the lines. He does condemn terrorism in serious terms, not the false CAIR Ibrahim Cooper way. However, he loves to take subtle shots at the US and holds nutty views about US culture. With respect to the former, in one speech (available on Youtube) he subtly blamed the US for Saddam Hussein's invasion of Kuwait (ignoring that Saddam was given an opportunity to prevent the Gulf War by withdrawing his troops from Kuwait, but of course Islamists never mention that crucial fact), blamed the US (and the UK, France, and Russia) for Saudi Arabia's defense budget (as if the US forces Saudi Arabia to buy weapons and as if Saudi Arabia does not have legitimate fears of Iraq and Iran), and took an obligatory shot at US support for Israel. Regarding the culture and society, I remember him condemning G rated movies based on a nutty conspiracy theory only a tiny percentage of fundamentalist Christians believe. He legitimately criticized some things in the US, such as the problem of tens of millions of uninsured people, but implied that this was because of an inferior moral system to Islam, as if Islamic societies place a big emphasis on social welfare (the best welfare states are very secular Christian Scandinavian countries). Last but not least he claimed "America needs Islam." That is respectful? This is what passes for a "moderate" American imam? Saying "America needs Islam" is based on a condescending view of America, a colonial attitude that holds the existing society is inferior and "needs" to be changed by foreign forces to civilize it. And this is just a case study of one speech from one major imam!
There are legitimate moderate--and even a few liberal--Muslims but the problem is they are not ones who get involved in mosque affairs or organizations like ISNA. They may go to the mosque now and then but they won't run for treasurer of a mosque and help shape it.
I do agree that the average Muslim can do nothing to stop terrorism because terrorists are underground. It is not as if Al-Qaeda operatives walk into mosques with Al-Qaeda insignias on their thobes. What the average Muslim can do, though, is fight the ideology of radical Islamism. There are many ways to do this. For one you can do it online at places such as this. You can do it at the mosque, at doctor X's dinner party, on EID at family gatherings. Let's be real here. Every Muslim family (meaning extended family, not just parents and siblings) has at least a few Islamists in it. Their ideology must be fought with truth and reason. Sadly, many non-Islamist Muslims are silent when their cousin the Islamist begins ranting about the utopia Islamism allegedly would lead to.
Let’s get real. Since when were civil liberties a cherished ideal of Islamists? The only reason CAIR cares about them is because they are opposed to strong law enforcement efforts against terrorism.