Is Real ID (with the gold star) required to fly if you don't have a passport? Or is a US ID without the star sufficient if flying within the USA?

On October 1, 2020, the Real ID will be required if you would like to use your State Issued ID/Driver's license to fly within the United States. This requirement is a more thorough identity validation executed by each state. I am unaware of a national ID, besides a passport. Regular state IDs (without the Star) are valid until next year.

October 2020 is when you will be required to have Real ID or a passport.