Which Arab regimes, today, are "US installed"? Iraq is the only plausible answer.
As far as stability, I don't know. My view is that Arab democracies are unstable because they will elect Islamists. Dictatorship/monarchy has proven far more stable. Syria is trying to buck the trend; we'll see how it goes.
> Arab democracies are unstable because they will elect Islamists.
why does that imply instability?
Maybe more accurate to say “Western-installed” although generally I don’t like grouping Europe and the US together as some coherent entity in this case it’s probably accurate.
All of the Gulf monarchies as well as Jordan are essentially western creations that were created as states mostly by the British and then heavily reinforced by the US from the 70s onwards