While reading an article they mentioned in it that Shia Islam has a negative view on islamic expansionism and does not approve of the Sunni Caliphates aggressive expansionism throughout history. Particularly the Abbassids.

Is there any truth in this? My own searches did not find anything. Historically, has sunni islam been more expansionistic than Shia islam? Was Shiites opposed to this? If Sunni islam has had a more expansionist focus, was this simply because it was more powerful and had opportunities that shiites simply couldn't match? Or was it because of ideological/societal differences, if so which?