Get an experienced Trump whisperer in to back the silly old bugger out without feeling as though he lost.

It's a mental health issue, and if you can't reel him in with gilded trinkets you'll need some cooler heads to remove him from issueing executive orders and immediately pass control to congress.

The time for fixing the flaws in the US system was 20+ years past .. but if you can get that effort in now, it'll be appreciated.

Accept that you lost. Apologize for the mistake. Pay a few billions for repatriations, lift sanctions and open dialogue. But engaging into a multi-year trillion war is more likely, than accepting defeat upfront