Karl Rove, the bete noir for Democrats (and some Republicans), has dared to raise questions about Hillary Clinton’s health.

The New York Post first reported a conversation between Rove, former White House Press Secretary Robert Gibbs and Dan Raviv of CBS News about Mrs. Clinton’s fall and concussion in December 2012. Rove was quoted as saying, “Thirty days in the hospital? And when she reappears, she’s wearing glasses that are only for people who have traumatic brain injury? We need to know what’s up with that.”

Bill Clinton defended his wife saying she is “in better shape” than he is, but confirmed that it took “six months” of “very serious work” to recover from her concussion. A State Department spokesperson said it was 30 days. Which is it?

The physical condition of a president, or one seeking the office, is a fundamental issue in any campaign and in every presidency. Virtually every president since George Washington has had health issues, some minor, some major. Not all presidents or their staffs were forthcoming about them.

In 2002, The Atlantic Monthly compiled a list of presidential health cover-ups: “Concealing one’s true medical condition from the voting public is a time-honored tradition of the American presidency. William Henry Harrison, who died of pneumonia in April of 1841, after only one month in office, was the first chief executive to hide his physical frailties. Nine years later Zachary Taylor’s handlers refused to acknowledge that cholera had put the president’s life in jeopardy; they denied rumors of illness until he was near death, in July of 1850, sixteen months into his presidency. During Grover Cleveland’s second term, in the 1890s, the White House deceived the public by dismissing allegations that surgeons had removed a cancerous growth from the president’s mouth; a vulcanized-rubber prosthesis disguised the absence of much of Cleveland’s upper left jaw and part of his palate. The public knew nothing about the implant until one of the president’s physicians revealed it in 1917, nine years after Cleveland’s death.”

Perhaps the most famous cover-up occurred with Woodrow Wilson. In 1919, during his second term, Wilson embarked on a national tour to promote the World War I peace treaty he had personally negotiated. During the trip, Wilson experienced headaches and fatigue. The tour was aborted and Wilson returned to the White House where he suffered a stroke.

Wilson’s inner circle, including his wife, doctor, private secretary and even the secretary of state, hid his condition. They told the press and cabinet the president had suffered a nervous breakdown. No one was allowed to see him, not even his vice president. Wilson retired from the White House in 1921 and died three years later.

That sequence of events couldn’t happen in today’s saturated media environment. Or could it?

John F. Kennedy suffered from multiple health problems. Among the cover-up conspirators was Kennedy’s doctor, Janet Travell, who is credited with the idea of JFK’s rocking chair to ease his back pain and to convey a positive image.

Bill Clinton refused to release his medical records to the public. Barack Obama released a one-page letter from his doctor testifying to his “excellent health.” Both men admitted to using recreational drugs in their youth, though Clinton ludicrously claimed he didn’t inhale. Obama smoked cigarettes.

Just as most candidates for high office feel compelled to release their tax returns (Mitt Romney was a rare exception), all candidates, especially candidates for president, should publish their medical records.

If Hillary Clinton’s concussion was not serious and there are no concerns about its long-term effects; if the glasses she now wears are not to correct double vision or other lingering symptoms attributed to her fall, then there is no problem. But if the reverse is true and she is covering it up, the public has a right to know and she has a duty to tell us. The media also have an obligation to keep up the pressure until the truth is known.

Cal Thomas is a syndicated columnist and author. Readers may email him at: tcaeditors@tribune.com.