What are our national interests in Ukraine? There are none. What are our national interests at our souther border? There are plenty, beginning with a nation is only a nation with clearly defined and controlled borders. A nation without control over its borders is not a nation. We no longer have a country. Biden does not enforce laws established by our elected representatives.
Ukraine has become the new quagmire. Get out of one endless war (Afghanistan) and jump into another. We are the biggest debtor nation and it only gets worse.