A special edition of the Herald newspaper focuses on the crisis in Zimbabwe. (AFP via Getty Images)

Military vehicles were stationed across Zimbabwe's capital early Wednesday, with the country's longtime leader under house arrest. But is it a military coup? Not at all, according to the military.

“We wish to make it abundantly clear that this is not a military takeover,” said a televised statement read by Maj. Gen. Sibusiso Moyo, adding that the military was targeting "criminals" around President Robert Mugabe "who are committing crimes that are causing social and economic suffering in the country.”

There are certainly those in Zimbabwe who seem to agree. On Twitter, journalist Maynard Manyowa described scenes of calm in Harare. "No coup here," Manyowa wrote.

But outside the country, observers aren't so sure. As footage of the situation in Harare spread, Ugandan writer Charles Onyango-Obbo offered a blunt assessment in a message to Zimbabwe's military. "If it looks like a coup, walks like a coup and quacks like a coup, then it's a coup," Onyango-Obbo tweeted.

The still-evolving situation in Zimbabwe highlights some of the complexities of defining what constitutes a military coup. Academic definitions of a coup vary, but there are some broadly accepted criteria: There must be the use or threat of force by people inside the government with the aim of seizing control over the national political authority. Some definitions also say that the plotters must use illegal means to seize power.

The sight of the army in Harare can certainly be read as a threat of force, but for now the military is claiming that it wants to keep the 93-year-old Mugabe in power — a detail that may mean that what's happening in Zimbabwe may not quite technically match the requisites of a coup, according to Jay Ulfelder, a political scientist who works for the technology company Koto and is an expert in political instability.

"Whatever the technicalities, though, they do seem intent on reshaping who wields power now and after Mugabe is gone," Ulfelder said, referring to the military's apparent attempt to block the 93-year-old's likely successor, his 52-year-old wife, Grace Mugabe. "So, even if Mugabe officially keeps his seat, the consequences of this intervention may amount to a coup, semantics aside."

Either way, the military's denials of a takeover aren't strong evidence against the idea of this being a coup. Such denials are a notable characteristic of many coups.

Jonathan Powell, an assistant professor at the University of Central Florida who studies coups, says that as far back as the Cold War, if not before, "coup" has been a dirty word.

"The military is almost invariably going to provide at least rhetorical justification to legitimize their actions," Powell said, noting that military plotters have often gone to great lengths to get a letter of resignation from an ousted political leader.

Naunihal Singh, an assistant professor at the U.S. Naval War College and author of a recent book on military coups, said that what is happening in Zimbabwe is a coup, no matter what the military says. "'The President is safe' is a classic coup catch-phrase," Singh wrote on Twitter. "No, I expect a transition in the next few days, whether dejure or defacto."

Events in Zimbabwe may end up being framed as a "guardian coup" — a term for when the military or another political force steps in to temporarily take control of a country during a time of danger. Zimbabwe is scheduled to hold a general election in 2018; as one supporter of the military's action put it, Wednesday's developments are a "bloodless correction" that would restore democracy to Zimbabwe.

That logic is reminiscent of another recent military takeover: the Egyptian military's move against President Mohamed Morsi in 2013 — when some even framed the coup as a good thing for democracy because it ousted an autocrat. A month later, Secretary of State John F. Kerry said the Egyptian military "was asked to intervene by millions and millions of people, all of whom were afraid of a descendance into chaos, into violence."

"In effect, they were restoring democracy," Kerry said.

In Egypt's case, the avoidance of the word "coup" had a financial component. Section 508 of the Foreign Assistance Act says the United States is required to suspend aid to nations that undergo a military coup, although the law's language leaves it open to interpretation. Though Zimbabwe receives only a small fraction of the aid that Egypt does, Powell said the country is likely to face sanctions from other entities, including the African Union and the Southern African Development Community, because of the alleged coup.

Powell suggested that military leaders may attempt to avoid these sanctions by pushing for a faster timeline for next year's election. But things may not necessarily work out that way — one study found that between 1991 and 2006, only 34 percent of coups resulted in an election within five years.

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