The US has previously worked to help reduce nuclear proliferation partly by offering security in exchange (e.g. Budapest Memorandum whereby Ukraine gave up their nukes). Of course there's a short term (& short sighted?) benefit to the US if it can reduce the military budget significantly, and/or redeploy assets from supporting NATO partners to areas felt to be more important to current US interests, BUT this comes at a cost ... NATO members, and others - like Ukraine - believing themselves to be under a US security umbrella will now realize that such promises mean little to nothing - having an expiration date at the end of the US administration that negotiated them - and they have to take care of themselves. Is it really in the US's long term interest to have ROW more heavily militarized and more countries developing/proliferating nuclear weapons for their own protection?

As far as technology goes, putting a hard embargo on US exports of AI-supporting hardware is only going to further accelerate China's push to develop home-grown alternatives, and in a world where the US is isolating itself and new alliances are forming, such as China-Russia, this means that future US attempts to prevent cutting edge technology getting into the hands of others will be increasingly futile since these non-US alliances will support each other.

An isolated USA is in the end a weaker USA.