No airbags are not mandatory on all vehicles. In the united states airbags are mandatory on vehicles under 8500 gvw(gross vehicle weight rating), but might be standard/optional equipment from the manufacturer.

The United States

1983

Some of the major exports of the United States are oil, plastics, pharmaceutical products and machinery. Other major exports are electronic equipment, vehicles and aircraft.

All vehicles sold in the US have a mandatory lifetime warranty on seatbelts, at least the mechanical parts. Don't think any electrical components are covered.All vehicles sold in the US have a mandatory lifetime warranty on seatbelts

I work at a dealership and can say for sure that not all vehicles have that. You will want to contact your local Ford dealer with your VIN number and they can check for any warranty or recalls.