Original sentence: The students were unwilling to defend a foreign government.They wanted to drive the British out of Singapore and with the communist influence the demonstration led to rioting when the police arrived to disperse them and had to put down the riot, though with great difficulty
Edited sentence: The students were unwilling to defend a foreign government which, in World War 2, and when Singapore had most needed support, deserted them.They wanted to drive the British out of Singapore and with the communist influence the demonstration led to rioting when the police arrived to disperse them and the police had to put down the riot, though with great difficulty