The anti- Communist policy of the government under Menzies became electorally self-rewarding and they sought to use it wherever possible.
This does not deny that they were not totally convinced for the best of reasons but that they also managed to convince the electorate that Communism must be opposed wherever possible.
It was feared that this "domino" action would eventually lead to Australia's shores and then the policy of forward defence would mean the war would be in Darwin instead of Vietnam and Australia would be in imminent danger.
The involvement of Australian forces in Vietnam was a continuing development of increasing commitment that took place over a period of several years against a background of Cold War concerns with regional security and fear of Communist expansion.
The Australian Government was also concerned that United States involvement in the South East Asian area should be encouraged and supported in case of future threats in the region.
With this growing fear in mind, Australia had long suffered from a sense of unease about its position as the only European settled country in Asia.
The American presence in South Vietnam was seen as an extension of the principle of containment.
That principle had it that in the interests of avoiding a global war no great attempt would be made to liberate countries, which had fallen to communism, but the spread of communism, inevitably by dictatorial means, would be resisted.
Unless this aggressive action by China was stopped in Vietnam, the theory ran, that after Vietnam had fallen, the surrounding countries would follow, just like a row of Dominoes.
These countries, which tended to be neutral in their outlook, favouring neither east nor west, might become involved in another war like Vietnam, or they might defect to the Communist line.