Original sentence: The Americans also depicted the motivations and timings of the Cubans differently: They claimed that South Africa had to intervene after Cuba sent troops in support of the MPLA and that the war in Angola was a major new challenge to US power by an expansionist Moscow newly confident following communist victories in Vietnam War.The US assumed that the USSR was behind the Cuban interference
Edited sentence: Of course the US assumed that the USSR was behind the Cuban interference.The Americans also depicted the motivations and timings of the Cubans differently: They claimed that South Africa had to intervene after Cuba sent troops in support of the MPLA and that the war in Angola was a major new challenge to US power by an expansionist Moscow newly confident following communist victories in Vietnam