They're not supposed to. All that "infrastructure" nonsense the left talks about is not their responsibility. That includes federal, state, county and city governments. They claimed that responsibility a long time ago and because of that we just accept that this is what the government is supposed to do.
And now "infrastructure" is the word Dems use to steal more money from us. The feds give about 50 cents to actual infrastructure and keep the rest for their own use.