The Countering America’s Adversaries Through Sanctions Act (CAATSA) aims to sanction nations that do business with Iran, North Korea, and Russia. Defense Secretary James Mattis is urging the broad use of exceptions for US allies who are buying Russian arms.
The problem is fairly straightforward. The US is the world’s largest arms exporter, with Russia a distant second. CAATSA sanctions, however, risk chasing off potential customers who are already buying some equipment from the Russians.
In some cases, countries the US are courting as customers, like Indonesia, have to buy parts from Russia to keep their existing systems in place. Other important customers, like India, Vietnam, and Turkey, all buy from both the US and Russia. The concern is, if the US makes them choose one or the other, they might choose Russia, and find other NATO partners for the US-style equipment.
The US has reacted angrily in recent years when customers buy new Russian gear, as with Turkey acquiring the Russian S-400. Despite being the market leader in arms, however, Mattis’ comments recognize that the US can’t enforce a monopoly in any real way.