A seemingly innocuous habit of leaning against walls, railings, or doorways can instantly identify Americans overseas, according to a former CIA official.

Jonna Mendez, the agency's former Chief of Disguise, stated that intelligence officers were trained to avoid this posture, known as the "American lean," during undercover missions abroad to prevent their cover from being blown. Mendez explained that Americans are often perceived as more relaxed and informal than people in other countries, with their casual posture and tendency to lean making them stand out.

In contrast, people in many other countries tend to stand more upright and avoid leaning on objects in public spaces, especially in crowded areas where taking up extra room is discouraged. This subtle difference in body language can be enough to draw attention from locals or make it easier to spot undercover operatives attempting to blend in.

Mendez noted in a Reddit "Ask Me Anything" session that Americans can also be identified by other behaviors, such as being perceived as more casually dressed and louder in public compared to other nationalities. She suggested that Americans often stand out by the amount of noise they make in public spaces.

Beyond posture, Mendez highlighted other cues that can reveal an American's origin. She mentioned that wedding ring placement can differ, with many European countries wearing them on the left hand's fourth finger, similar to the U.S. tradition rooted in the belief of the vena amoris. However, in much of Central and Eastern Europe, including Germany and Russia, wedding rings are traditionally worn on the right hand, often linked to religious customs.

Mendez also observed differences in dining habits, stating that Americans may shuttle their forks back and forth while eating, unlike the practices in some other cultures. For most travelers, these habits are harmless, but for undercover operatives, adopting local mannerisms, including how they stand and carry themselves, is crucial for maintaining their disguise.