So Ukraine is fighting a war for democracy against Russia, thereby fighting for all of us. .

and folks like Robert Reich wonder why we aren't providing government housing and free lunches to children all over the country.

A sandwich and a HMARS. These are not the same.

Well, that's fairly easy.  "Provide for a common lunch" is actually not a logical equivalent to providing for the common defense.

Indeed, as hard as it is for people to accept it, that really isn't an obligation of the Federal government,  providing an army to defend the country is, and if we can fund somebody else to fight a war, so we don't have to, all the better.

And if a foreign war is in the national interest, existentially, as it's a contest between our values, and those of something we're deeply opposed to, well, we should support them and only the Federal Government is well situated to do so.

The added part of this is that by and large, social programs tend to become social rights and then social failures.  In much of the country the school districts in fact provide free lunches, which morphed into free breakfasts, which as morphed into a societal right for people to refuse to feed their children, as the districts have to.