If he watches more of those Chinese cartoons he will become……

As far as I'm aware Adolf Hitler never hated the Japanese as he saw them as another race of people who belong to their own respective civilization.
Necessity was of course the main driving reason, but he did share these thoughts in his political testament;
Pride in one's own race – and that does not imply contempt for other races – is also a normal and healthy sentiment. I have never regarded the Chinese or the Japanese as being inferior to ourselves. They belong to ancient civilizations, and I admit freely that their past history is superior to our own. They have the right to be proud of their past, just as we have the right to be proud of the civilization to which we belong. Indeed, I believe the more steadfast the Chinese and the Japanese remain in their pride of race, the easier I shall find it to get on with them.