> If this information is beneficial to both sides, it should be freely exchanged. A lot of it is. You still want independent confirmation of these things. It

> If this information is beneficial to both sides, it should be freely exchanged. A lot of it is. You still want independent confirmation of these things. It reduces incentive to lie (by increasing the probability of being caught), and can mitigate some types of miscommunication. E.g. maybe your ally can't admit something that they know to be true, because it happens to be unpopular domestically. I'm not sure that this is sufficient justification, but the benefit does exist. > If this is a necessary element of state diplomacy, how can interactions between countries like the US and Mexico ever be fair? How can they ever be fair if it isn't? Fairness is just not a property that interactions generally have. Every actor has advantages, and those advantages are rarely equal for all parties.