Did the domino theory lead to vietnam?

To be blunt,the idea of theory,reason,and response to communist aggression in regards to U.S involvement within Vietnam is simply non existent; Vietnam was a raw and disturbing preview of the political dishonesty and corruption pulsing through American government today. Theory and all that jazz merely shadowed true intention of U.S involvement. If any man's idea or theory had a direct impact on U.S involvement in Nam that man was Lindon Johnson coupled with his "foreign policy"