Trump went on to claim that Muslim spiritual and organizational leaders are refusing to tip off law enforcement authorities as to the dangers of would be jihadist mass murderers, stating ominously: "The Muslims have to work with us. They know what's going on."

And Thursday night, Trump claimed that "there's no real assimilation," even among second- and third- generation American Muslims.

These are offensive and divisive myths. Muslims assimilate remarkably well into the United States. And the vast majority of American Muslims are strongly opposed to extremism and terrorism, and are doing everything within their power to fight an evil ideology that seeks to hijack the noble religion of peace and brotherhood to which they adhere.

Our own organization, the Foundation for Ethnic Understanding, recently launched a national campaign entitled #MASO - Muslims Are Speaking Out - to make the point and promote to the media that all of the major American Muslim organizations, as well as hundreds of thousands of grassroots American Muslims, are speaking out loudly and unambiguously against terrorism, hatred and bigotry.

Muslim leaders like Hassan Shibly, executive director of the Florida chapter of the Council on American-Islamic Relations (CAIR), were meeting with family members of the predominantly gay and lesbian victims of the Orlando massacre to offer comfort, hugs and prayers. Shibly told Time magazine that what he had felt during his meetings with the families of victims was "overwhelming love, support and unity."

The Fiqh Council of North America, the highest body of Islamic jurisprudence in the U.S. and Canada, stated authoritatively in the wake of the massacre: "There is no justification in Islam for extremism or terrorism. Targeting civilians' life and property through suicide bombings or any other method of attack is haram or forbidden - and those who commit these barbaric acts are criminals, not martyrs."

And even as a panoply of national American Muslim organizations including CAIR, the Islamic Society of North America, the Muslim Public Affairs Council and the United States Council of Muslim Organizations held press conferences in Washington to denounce the mass murders, LaunchGood hosted a fund-raising campaign, which as of Thursday evening had raised more than $69,000 from American Muslims for the families of the shooting victims.

This galvanizing response should make evident to all clear-thinking Americans that the American Muslim community is our essential ally in the fight against ISIS. Indeed, every day, imams across America are reaching out to young Muslims inside and outside their mosques to prevent these impressionable young people from being seduced by the online siren call of radical jihadism.

Yet those efforts are being undercut by political leaders who seem intent upon giving these same young Muslims the message that America hates their religion.

One of the central tenets of Islam, as of Judaism, is the belief that "Whoever kills a person (unjustly), it is as though he has killed all mankind. And whoever saves a life, it is as though he had saved all mankind" (Koran, 5:32).

Let all Americans of good will - whether Muslim, Jewish, Christian or other, male or female, gay or straight - stand united in support of that principle and in affirmation of our common humanity.

Schneier and Simmons are president and chairman of the Foundation for Ethnic Understanding.