Any close look a the concept & usage of the term ‘US regime-change operation” shows it to be only thing even approximating a theory among the most demagogic or backward political currents. It substitutes analyses of complex political & social struggles with conspiracy theories involving nefarious forces & intrigues. Those nefarious forces include the CIA, Mossad, Zionists, ‘Islamists’. It’s not that the CIA, et al, are not engaged in undercover destabilizing operations but that proponents of the “US regime-change operation” mantra see all popular struggles against repression as those undercover operations writ large.
The mantra is actually more of a battle cry for right-wing forces posturing as left-wing avant-garde (Stalinists, fascists, Assadists & that political ilk) because most of all, it serves to defend the status quo of state power & repressive regimes & malign popular struggles for democracy, & against war, occupation, & genocide.