I'm pretty sure we're in the top 5 for gun exports, too. If the US government killed the US gun/ammo industry, they'd not only lose their own suppliers, but a massive revenue stream from exporting weapons to Middle Eastern terrorists. A buddy of mine works as a DCMA in the Colt factory and he said he's got the most secure job on the planet. He works as the representative for the US government in a factory that supplies weapons to his bosses and their enemies. The only big time foreign importer for M16s is Fabrique Nationale of Belgium, but I'm almost positive they have American factories to supply the US feds.
I also heard that Federal, one of the biggest US ammunition suppliers, put their civilian orders on the backburner to supply Saudi Arabia with a large order. It may not seem like a big deal, but if you're a US citizen and keep up on gun shit, this is infuriating. We get it when ammunition droughts are extended due to their government contracts, but Saudi Arabia? Weren't like 18 of 22 9/11 terrorists Saudi? How we keep sucking their cock is fucking beyond me, Trump included.