WASHINGTON - A noted American columnist has denounced a Republican presidential contender for demonising Islam and called for and an end to his 'bigotry.' "It is time to stop giving Herman Cains unapologetic bigotry a free pass," Eugene Robinson wrote in The Washington Post, referring to the presidential candidate, who is the only African-American among the Republican hopefuls. "The man and his poison need to be seen clearly and taken seriously," columnist Robinson, also an African-American, wrote after Cain said on national television that voters across the United States should have the right to prevent Muslims from building mosques in their communities. Robinson wrote, "Imagine the reaction if a major-party presidential candidate one who, like Cain, shows actual support in the polls said he wouldnt be comfortable appointing a Jew to a Cabinet position. Imagine the outrage if this same candidate loudly supported a communitys efforts to block Mormons (an offshoot of Christianity) from building a house of worship. "But Cains prejudice isnt against Mormons or Jews, its against Muslims. Open religious prejudice is usually enough to disqualify a candidate for national office but not, apparently, when the religion in question is Islam. "On Sunday, Cain took the position that any community in the nation has the right to prohibit Muslims from building a mosque. The sound you hear is the collective hum of the Founding Fathers whirring like turbines in their graves. "Freedom of religion is, of course, guaranteed by the Constitution. Theres no asterisk or footnote exempting Muslims from this protection. Cain says he knows this. Obviously, he doesnt care. Cains remarks came as Fox News Sunday host Chris Wallace was grilling him about his obsession with the attempt by some citizens of Murfreesboro, Tennessee, to halt construction of a mosque.