The U.S. is, politically, regressing back into a state of sexual prudery that could potentially cancel out strides made toward sexual liberation and privacy, according to Hugh Hefner, who took to the pages of his own Playboy Magazine to blast repressed conservatives who he believes are pounding on America's bedroom door.

The magazine magnate, who is credited with advancing the nation's sexual revolution with the introduction of his men's magazine in the early 1950s, penned a rare editorial titled The War Against Sex in Playboy's May issue, according to Politico.

Hefner took issue with the rhetoric used by Republican presidential candidates as they attempt to one-up each other on their conservatism. He specifically blasted Rick Santorum's pledge to defund birth control on the grounds that contraception is a license to do things in a sexual realm that is counter to how things are supposed to be, as well as Mitt Romney's vow to see through a constitutional amendment to ban same-sex marriage, and overturn the Supreme Court's 1973 decision on abortion in Roe v. Wade.

All these years later, I hear echoes of this same ignorance espoused by a new crop of self-appointed arbiters who are determined to oversee our morality, Hefner wrote. I heard it when Santorum backer Foster Friess said, 'Back in my days, [women] used Bayer aspirin for contraceptives,' implying that if women held an aspirin between their legs, they wouldn't open them.... And I heard it when Rush Limbaugh called a Georgetown University law student a 'slut' and a 'prostitute' after she testified on Capitol Hill about allowing employers to avoid providing contraception for religious reasons. ... Fifty years of sexual freedom vanished in a sound bite.

Hefner concluded that wide-scale public action is needed to combat the professed goals of conservative zealots.

If these zealots have their way, our hard-won sexual liberation -- women's rights, reproductive rights and rights to privacy -- lie in peril. We won't let that happen, he wrote.

The 86-year-old Hefner has been challenging the nation's attitude about sex since 1953, when the first Playboy Magazine hit stands featuring Marilyn Monroe wearing nothing but a come-hither look.

On Monday, Hefner officially bid goodbye to his hometown of Chicago in a column published in the Chicago Tribune. Playboy Magazine officially closed its Chicago offices as part of a plan to consolidate its operations in Los Angeles.