ULA will probably end up encouraging Bezos to build a complete rocket. There are some other players talking about using the BE3 (the tourist rocket engine) as an upper-stage engine, and ULA is likely to use the BE4. At that point, Bezos can market the complete rocket as &quot;You already depend on our engines, why not try our complete rocket?&quot;<p>You can&#x27;t really &quot;capture&quot; a billionaire&#x27;s business.