The vulnerability of Singapore was deeply felt, with threats from multiple sources including the communists and Indonesia with its confrontational stance. As Singapore gained admission to the United Nations, Lee quickly sought international recognition of Singapore's independence. He asked Goh Keng Swee to build up the Singapore Armed Forces (SAF) and requested help from other countries, particularly Israel,[39] for advice, training and facilities. Lee introduced conscription whereby all abled-bodied male Singaporean citizens age 18 and above are required to serve National Service (NS) either in the Singapore Armed Forces, Singapore Police Force or the Singapore Civil Defence Force.