 Complete the following phrase:  The impact of the security forces decisive counter-campaign was to be undone by two drastic changes to the geopolitical situation in 1974 and 1975, each relating to one of the Rhodesian governments two main backers, Portugal and South Africa. In Lisbon, a military coup on 25 April 1974 replaced the right-wing Estado Novo administration with a leftist government opposed to the unpopular 