(CNN) -- Sen. Rick Santorum, who is campaigning to become America's second Catholic president, disagrees from the bottom of his gut with the first Catholic to hold the office. In October, he told a Catholic university audience that when he read the 1960 speech in which John F. Kennedy said: "I believe in an America where the separation of church and state is absolute," he "almost threw up." More recently, he elaborated on his dyspeptic condition in an ABC television interview, calling JFK's credo "an absolutist doctrine that was abhorrent at the time of 1960." But the Baptist ministers who witnessed Kennedy's speech surely felt differently. In the 1960s, evangelical leaders were not concerned that Kennedy was too secular; they were concerned that he was too Catholic.
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Michael Wolraich: Protestants were deeply wary of Catholics for most of U.S. history
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In 1960, he writes, evangelicals feared JFK's Catholicism more than secularism
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Wolraich: But a common enemy, secular authority, has united evangelicals and Catholics
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Doctrinal divisions could rise again, he says, and put Catholics on the defensive
But @placeholder was only 2 years old when they were spoken.