“Hard Choices” by Hillary Rodham Clinton; Simon & Schuster (635 pages, $35)

She hasn’t decided yet.

Or if she has, she’s not telling.

But if Hillary Rodham Clinton does run for president in 2016, her new book “Hard Choices,” a chronicle of her four years as secretary of State, leaves no room for doubt about how she might conduct foreign policy (pragmatically), how she will defend herself against charges that she mishandled the attack on the American compound in Benghazi, Libya (robustly) and about how much she regrets giving President George W. Bush carte blanche to wage war against Iraq (deeply and eternally).

Other regrets: Her inability to persuade President Barack Obama to arm the Syrian rebels early on in that country’s devastating civil war, failing to act more forcefully to support Iran’s pro-democracy demonstrators during the Green Revolution in 2009, and wrongly believing that Egyptian President Hosni Mubarak, who resigned after weeks of convulsive protests in Cairo’s Tahrir Square, was “stable.”

“Hard Choices” is a richly detailed and compelling chronicle of Clinton’s role in the foreign initiatives and crises that defined the first term of the Obama administration — the pivot to Asia, the Afghanistan surge of 2009, the “reset” with Russia, the Arab Spring, the “wicked problem” of Syria — told from the point of view of a policy wonk.

“We needed a new architecture for a new world,” she writes of her mission as American’s diplomat in chief, “more in the spirit of Frank Gehry than formal Greek classicism.”

She writes that she was genuinely surprised when Obama, her rival in the bitter 2008 Democratic presidential primary, chose her as secretary of State. But their reconciliation had begun months earlier, on June 5, 2008, even before his official nomination, when they met over Chardonnay at the Washington home of California U.S. Sen. Dianne Feinstein. “We stared at each other like two teenagers on an awkward first date,” she writes.

They had a candid discussion of what she calls a “long lists of grievances” about each other. But this hatchet was important to bury; Obama needed her help in the general election, and he needed Bill Clinton’s help, as well.

She tells of only one dressing-down by Obama, who was angry that an American envoy to Egypt, a man she had brought to the job, publicly discussed his differences with the White House over how to handle Mubarak. Obama, she writes, felt world leaders were getting a mixed message from Americans, and “took me to the woodshed.”

This memoir is a valuable account of Clinton’s time as America’s chief diplomat. It could remain just that — a chronicle for students of history and politics. Or it could become a political document, used to persuade voters she’s fit to be leader of the free world.

Whatever she decides about 2016, no one can say she’s unprepared for the job.