The US could be using these models to fix bugs and defend out systems.. but instead, we're all waiting for open source models to exceed the best unbanned model available in the US(0), and then we can all watch while attackers -- who can use any available open source model, including banned models -- to attack every US company on the internet.
US bans are a choice: a choice to lose to China; a choice to leave US companies defenseless; a choice to reduce competitiveness of the US in software. Every time a US person or company watches someone use models they are prohibited from using to achieve something US models can't, they create opposition to this ban. I can't imagine this is a sustainable policy.
0. Currently open source models are included in consideration for the "best model in the US" -- but if they're willing to ban the best from Anthropic/OpenAI, I wouldn't necessarily assume that all open source models will always be available within the US.