With respect, I don't think "hate" is the right word. Nor even is the term "strong dislike" despite dislike of body odours (and believe that or not it is 100% true) and lack of respect shown for local customs. Nor even is it a case of how well you treat someone. It's more a case that they just tolerate westerners.

i think it's important to remember a bit of the history of the continent. The Japanese waged a monstrous war against America and some of its Asian neighbours - and lost. The French committed unbelievable atrocities against its colonial vassal states of Laos, Cambodia and Vietnam. When they were kicked out in 1954, along came the US and its allies with even more atrocities and millions murdered (the tiny landlocked country of Laos is the most bombed per capita in history - between 1964 and 1973 the US dumped a planeload of bombs on it every 8 minutes for 9 consecutive years!) The British record in colonial Malaya is nothing to be proud of. China all but imploded with millions killed and the country set back many decades with the disastrous Cultural Revolution which ended just 41 years ago.

Add in to that mix of horrors the fact that the vast majority of peoples in Asian countries had had absolutely no connection whatever with westerners until this time - and the example the foreigners set was not pleasant. You therefore have to set this "tolerance" for foreigners against a backdrop of virtual isolation against colonial oppression which morphed into a virtual holocaust.