Party of Australia. At the 1949 election, Wentworth was elected to the House of Representatives for Mackellar in the northern suburbs of Sydney. By the late 1940s Wentworth had become a fierce anti-Communist, to an extent that even some in his own party regarded as excessive (though Menzies was more than willing to benefit from his frequent red-baiting): he was frequently accused of McCarthyism in making allegations under parliamentary privilege, usually unsubstantiated, of Communist influence in various quarters of Australian public life. He was a leading member of the "Taiwan lobby" in the Liberal Party, which also included Wilfrid Kent Hughes and the young John Gorton. He frequently sought to imply that the leader of the opposition Australian Labor Party, Dr H. V. Evatt, was a communist sympathizer, or at best a dupe of the communists. The communists, he said, wanted to "ride into power on the back of the Australian Labor Party". Menzies's biographer referred to him as "the notorious Liberal Party backbench red-baiter". Wentworth, however, was more than a one-issue politician, and had great energy and ability. As Gorton's biographer writes: "For all his erratic and sometimes bizarre behaviour, his flaws were at least those of an inventive mind". Despite this, he had a long wait for ministerial preferment, mainly because he was a party-room rebel on other matters, such as pensions. During these years he busied himself with parliamentary committee work. He was an active member of the Foreign Affairs Committee from 1952 to 1961. From 1956 he was chair of the Government Members Committee on Rail Gauge Standardisation. He made important recommendations on solving one of Australia's longest-standing infrastructure problems, the incompatible rail gauges in the different states, a legacy of colonial times. Gough Whitlam, no admirer of Wentworth in other respects, credited him with being one of the architects of the rail standardisation agreement that led to the opening of the single-gauge rail line from Melbourne to Sydney in 1961. On the wider front, however, the head of the South Australian Railways observed that "despite his undoubted enthusiasm for railway matters, Bill Wentworth’s intrusion into the debate and his advocacy for nothing more than inter-capital links doomed forever any chance of an integrated standard gauge rail network being achieved. It is a pity that he ever became involved." Wentworth's other long-term interest was in Aboriginal affairs. In 1959, he put forth a proposal to Cabinet