What was Australia doing in Vietnam?

Australians had good reason to believe in the domino theory

In July 1967 President Lyndon B Johnson sent two of his principal advisers, Clark Clifford and Gen Maxwell Taylor, to Australia and New Zealand with an urgent mission. Protests were raging in American streets and on university campuses. Hawks and doves were battling in Washington. Defence Secretary Robert McNamara was heading toward resignation, an admission that his Vietnam policy had failed.

Amid this turmoil, Gen William C Westmoreland was demanding a substantial escalation in American troop numbers, around 400,000 at the start of the year. To get any increase out of an increasingly critical Congress, Johnson had to show that American