Late Tuesday night, news broke that Iran had detained 10 American sailors. Despite all available evidence indicating that the sailors were detained because they accidentally drifted into Iranian waters, along with statements from US government officials saying the sailors would be released shortly, conservative politicians and writers immediately began blaming the situation on Obama's "weak" and "feckless" foreign policy:
If our sailors aren’t coming home yet, they need to be now. No more bargaining. Obama’s humiliatingly weak Iran policy is exposed again.— Jeb Bush (@JebBush) January 12, 2016
Ted Cruz: Iran Detaining Sailors ‘A Demonstration of the Unbelievable Weakness of the Obama-Clinton Foreign Policy’ https://t.co/lWREJgCojs— Breitbart News (@BreitbartNews) January 13, 2016
Hey Iran, you have exactly 300 days left to push a US president around. Enjoy it while you can. After that, there will be hell to pay.— Joe Scarborough (@JoeNBC) January 12, 2016
Wednesday morning, Iran — as expected — released the American sailors. What does that say about the idea that American "weakness" is encouraging Iranian aggression?
To find out, I called up Robert Farley, a professor of international relations at the University of Kentucky. Farley tweeted a bunch of interesting thoughts on this subject as the incident unfolded, including a revealing comparison to the time in 2007 when Iran seized a number of British sailors and held them for 13 days. In our phone call, he explained why the theory claiming that signals of American "strength" are the only way to deter enemies is fatally flawed.
"You're just trying to say that you're strong," Farley explained, "but the other state may just think that you're being an asshole."
What follows is a transcript of our conversation, edited for length and clarity.
Zack Beauchamp: Would you describe the way yesterday's situation was handled as a "normal" diplomatic resolution to the incident?
Robert Farley: Yeah. I would describe this as not outside of the norm.
The Iranians have posted some pictures [of the sailors], and the pictures do look aggressive. But from the information we have now, both sides acknowledge that there was some violation of Iranian territorial waters. Both sides acknowledge that the violation was accidental, based on some equipment breakdown on the US boats.
Polite powers manage to resolve these kinds of issues without actually arresting and seizing and pointing guns at each other. This is not an egregious international incident; it's taking them briefly, then returning the sailors and the boats.
ZB: As you mentioned in your tweet, in 2007, Iran took British sailors into custody for doing essentially the same thing (accidentally entering Iranian waters) as the American sailors did on Tuesday. Yet the American soldiers were released within one day, while the British soldiers were held for days.
RF: Thirteen days.
There were 15 of them, they were seized, and they were used in a variety of different photo ops. They were imprisoned; some of them claimed they were tortured while they were in prison. Moreover, it was very clear that they were not engaging in any hostile behavior toward Iran. They were hunting down some smugglers, or something along those lines. But they weren't engaging in reconnaissance or anything else that should have raised Iranian hackles beyond just the basic protection of their territorial waters.
So really the Iranian behavior was vastly more aggressive [in 2007] than it was in this latest incident. If you recall, at the time, Great Britain was a full partner [of the United States] in Iraq. Their armed forces were deployed in southern Iraq and elsewhere. So they were an alliance partner [in a war in which Iran was supporting the other side].
ZB: And yet, in 2007 the US approach toward Iran was much more hostile than it is today — that is, signaling "strength" rather than "weakness."
RF: If you recall, back in 2007 it was commonplace in the United States to talk about aggressive military action against Iran.
You were getting these "18 months until a bomb" articles — the same sort of articles we've been getting since the 1990s. But there were some particularly well-read ones that were coming out at the time. And so this discussion of engaging in direct war against Iran, which was not just about the nuclear issue but also about Iran's facilitation of Shia militias in Iraq, was sort of all the rage.
So I think it's fair to characterize the US relationship with Iran and US policy toward Iran as quite belligerent in 2007.
ZB: So if the idea that US "weakness" caused yesterday's situation doesn't really fit the facts, where does the idea come from?
RF: Most recently, from opponents of the US-Iran nuclear deal. But the idea that weakness begets aggression has a pretty long heritage, back to the  Munich Conference — which is of course this huge analogy that we use for every damn thing in American politics.
But it also has some scholarly lineage, through Thomas Schelling and some other people — this idea that if you send signals of weakness to a potential aggressor, that aggressor will pick up on the weakness and then become more aggressive in small or large ways.
The folks who are tweeting all about this are quite clear that they think the nuclear deal demonstrates weakness. So by demonstrating weakness, we then enable Iranian aggression — we suggest to them that we're pushovers, and that their actions will not be met by firm resolution. And so everything that happens after the deal with Iran becomes the fruits of appeasement, including an incident like this.
ZB: I get that this makes a certain kind of sense, in theory, but is it actually true? Does signaling "weakness" through diplomatic overture actually embolden Iran — or China and Russia, for that matter?
RF: It makes a certain amount of sense — as long as you don't look at most of the evidence.
If Iran had not, in fact, seized sailors in 2007, and we didn't have clear evidence that Iran had done this kind of thing before, then maybe it would kind of make a little bit of face sense. "Oh, look, they took our sailors, and they took them right before the State of the Union, so that must be an indication of weakness."
If we apply this to Russia as well — and the same crew [of pundits and politicians] does — we somehow demonstrated weakness and thus invited a Russian invasion of Ukraine [in 2014]. But again, this only makes sense if you don't remember that Russia invaded Georgia in 2008.
Again with the Chinese. As long as you don't remember that China knocked down one of our airplanes in 2001, it makes sense to say that the things they're doing today are because of American weakness. It all depends on a very willful ignorance about the behavior of all of these countries in the very recent past.
ZB: And the statistical research backs up your argument, right? As far as I'm aware, there's no persuasive empirical international relations scholarship suggesting that signals of "weakness" (American or otherwise) embolden enemy aggression.
RF: All of the recent scholarship, going back the past 15 or 20 years, has said that there are dreadful empirical and even some theoretical problems with the "weakness" theory.
What scholars have found is that when states try to send messages of strength, like these are supposed to be, other states just don't understand them. That it's very hard to send fine-tuned messages to other states: You're just trying to say that you're strong, but the other state may just think that you're being an asshole. So to speak.
Trying to carefully calibrate a message that says, "We're tough and resolute, but we're not dicks," is really hard for states to understand. There's this incentive to lie all the time, on both sides.
There are also some psychological reasons that states just don't interpret the messages they're sent in the way that they should be interpreted. Nobody "owns" their own message. Other people get a right to interpret it, and they're not going to interpret it in the way that you want them to.
ZB: So what some Americans see as sending a signal of strength the Iranians might see as compensation for weakness. Or as outright hostility and aggression that itself demands an aggressive response, especially given the decades-long history of American intervention in domestic Iranian politics.
RF: That's right. There's evidence that they're going to interpret it the way they want to interpret it. If they want to believe that we're incorrigibly aggressive, then they'll see our actions as being incorrigibly aggressive.
If, on the other hand, they want to believe that we're a paper tiger, they'll see it exactly as you say: compensating for weakness.