The first Prime Minister of Singapore, Lee Kuan Yew, set for the fledgling state a non-aligned foreign policy, and amplified Singapore's non-alignment by making harsh anti-American comments in the media from late 1965 to early 1966. Lee's vitriol against the US administration was interpreted as an attempt to gain the acceptance of the non-aligned Afro-Asian camp, and also as calibrated to cause Whitehall to think twice before planning a military withdrawal from British bases in Singapore. Beyond these two reasons, which are part of standard analysis, Lee's understanding - derived from the Malaysian Prime Minister, Tunku Abdul Rahman - that US President Johnson had pledged to support Malays against Chinese in the event of a communal conflict in Malaysia and Singapore also drove Lee to project a hostile attitude towards the US in August 1965. After meeting US Assistant Secretary for East Asian and Pacific Affairs, William Bundy, in March 1966, Lee accepted that the Johnson-Tunku agreement did not exist and US-Singapore relations then improved significantly. Based largely on archival sources from the US and the UK, this article revisits the period of Lee's anti-American press campaign and draws new conclusions about the factors contributing to Lee's strong criticisms of the US.