Secretary of State John Kerry has a humble goal: Be the greatest Secretary of State ever and bring peace to the Middle East. In the wake of his "apartheid" comments, that goal has never seemed more distant.

Kerry's tenure, barely a year old, has been mixed. He oversaw a remarkable new agreement with Iran (that Hillary Clinton would like a little credit for). Mr. Magoo-like, he accidentally solved the Obama administration's conundrum in Syria, avoiding a potentially embarrassing vote against airstrikes on Capitol Hill. And he brought Israel and the Palestinian Authority together in an attempt to finally, at last, figure out a workable agreement for the tensions between the two.

Solving that final problem is both enormously aspirational and clearly Kerry's aspiration. In December, David Rohde chronicled Kerry's exhaustive first months of activism on the issue for The Atlantic. Meeting after meeting; flight after flight; celebration of small-but-significant accomplishments.

Over the last month, the effort has collapsed. Last week, Israel walked out of peace talks. And then, in a private conversation with the Trilateral Commission, Kerry warned that any solution that doesn't create an independent Palestinian state "winds up either being an apartheid state with second-class citizens — or it ends up being a state that destroys the capacity of Israel to be a Jewish state."

Reaction was swift and wide-ranging. Opponents of the administration like Texas Sen. Ted Cruz called for Kerry to resign. The conservative Emergency Committee for Israel did the same. House Majority Leader Eric Cantor demanded an apology. And it was a chance for those with their own political aspirations to weigh in: Joni Ernst, candidate for the U.S. Senate from Iowa demanded that Kerry "immediately resign." (Ernst was in the news more recently for her colorful campaign ads.)

It wasn't only Republicans and political opponents that criticized Kerry. The ambassador to Israel objected to the idea (if not the need for a two-state solution). New York Rep. Steve Israel said that Kerry was "just plain wrong." And Kerry's long-time Senate colleague Sen. Barbara Boxer tweeted that "any linkage between Israel and apartheid is nonsensical and ridiculous."

Kerry released a statement last night offering a sort of apology. "Israel is a vibrant democracy and I do not believe, nor have I ever stated, publicly or privately, that Israel is an apartheid state or that it intends to become one," Kerry said. He continued: "I have been around long enough to also know the power of words to create a misimpression, even when unintentional, and if I could rewind the tape, I would have chosen a different word" instead of "apartheid." It was a forceful statement, arguing that he wouldn't let his commitment to Israel "be questioned by anyone."

But the damage to his aspirations, at least over the short term, has been done. The peace deal has never been more distant during his tenure, and the public perception of his performance has perhaps never been lower. "When I asked a respected American diplomat whether Kerry’s activist tendencies were simply driven by his ego," Rohde wrote in his December profile, "he laughed and said all secretaries of state dream of winning the Nobel Peace Prize." Could still happen, but it has never seemed further away.