(Jewel Samad — AFP/Getty Images)

Have a close look at this morning’s coverage of the alleged Iranian plot to kill the Saudi ambassador to Washington, and you might come away with a not insignificant question: Why would the Iranian government try it?

The criminal complaint unsealed Tuesday against the alleged conspirators in the case, Mansour Arbabsiar and Gholam Shakuri, sheds little light on Iran’s possible motives. And U.S. officials have so far presented relatively scarce evidence about why they believe the alleged plot was actually directed by factions of the Iranian government.

Officials have said that they will be detailing the allegations to allies, and the United States is also weighing whether to take up the matter at the U.N. Security Council, according to Reuters news agency.

On Wednesday morning, Vice President Biden told ABC’s “Good Morning America” that the “first thing we do is make sure the entire world and all the capitals of the world understand exactly what the Iranians had in mind.”

For now, however, the allegations risk leaving the United States vulnerable in the court of opinion.

“Maybe things have really fallen apart in Tehran, or maybe there’s a radical group that wants to stir up the pot,” Robert Baer, a former CIA case officer in the Middle East and author of several books on Iran, told The Washington Post. “But the Quds are better than this. If they wanted to come after you, you’d be dead already.” 

It’s just “not typical of the Quds Force or [Iran’s Revolutionary Guard Corps] to operate in the U.S., for fear of retaliation,” Rasool Nafisi, an Iranian-American scholar, told the New York Times

The counter-argument, of course, is that while it may not have been a characteristic move by the Quds in the past, Iran might have seen reason to try it now, even if it meant turning to a purported Mexican drug cartel to make it happen. Add to the circumstantial evidence that Iran’s hostility toward Saudi Arabia is certainly waxing, as the Arab Spring has toppled or threatened to unseat longtime allies of both the Iranians and the Saudis from other countries in the region.

In a worldwide travel alert issued late Tuesday, the State Department said the United States believes that the plot “may indicate a more aggressive focus by the Iranian Government on terrorist activity against diplomats from certain countries, to include possible attacks in the United States.”

But was Iran’s real target, under this theory, Saudi Arabia or the United States? And if it was Saudi Arabia, skeptics might ask, weren’t there more logical targets than an envoy who is not a member of the Saudi royal family and who maintains a relatively low-key presence in Washington?

“There’s a question of how high up did it go,” one official said Tuesday of the alleged plot. “And the Iranian government has a responsibility to explain that.”

U.S. officials, in other words, are awaiting clarity. But they aren’t alone.