For me it was the unfortunate combination of liking history and being politically active.
I liked learning history as in terms of the interplay of economics, demographics, meteorology, technologies, and the institutions that arose in the midst of them rather than any Great Man. To learn the lessons of the past, what problems they solved and what new problems they introduced. Then to take them and use it to improve my country. Did I mention I was a fervent patriot - as in love of the nation as embodied by its people, and not just its symbols?
Well the more history I learned, the less it seemed like the lofty country I was taught. Unpleasant but still manageable. Ask what you can do for your country you know. Well that's where being politically active and looking into joining think-tanks and political groups taught me very quickly that there was no way to enact any change that could improve the lot of my fellow countrymen nor was there any way I wouldn't be persecuted for my ethnicity once the going went tough.
So not much reason to continue to stand by such a country.
Oddly enough, the person that really pushed me back into the China wumao camp was a white-Jewish American retired General Wesley K. Clark and the books "Why Nations Fail" and Dr. Eric Li. I used to read up, admired Clark during his stint and run to become the nominee of the Democratic party for President. I was looking for a strong, principled candidate that can go against Bush Jr. for his ILLEGAL WAR IN IRAQ and naively thought that there was a minute possibility of Bush, Cheney, and Wolfowitz being prosecuted for the illegal invasion. I liked Clark because of his stellar academic record from high school to his stint at the National War College he always graduated at the top of his class. Plus, he was a wounded combat veteran who served his country in the Vietnam War. He didn't get the nomination but continued to follow the man's political involvement with the Dem party, watched his speeches, read his books, opinion pieces and then his talk at Harvard University with a bunch of German diplomats and academic back in 2013 SECURITY CONFERENCE TALK
I kept hearing, learning from Clark that he's an admirer of China not just ancient China but also the leadership and governance of China under the helm of the CPC. I found him often times at odds with his peers especially in the business community of being bullish on the Chinese economy as the Gordon Chang like doom and gloom for the Chinese economy was being promulgated year after year.
The book "Why Nations Fail" written by a couple of economists made me think hard on the efficacy and efficiency of Democracy and why it has largely failed on many countries outside the west. Lastly, it was the TED TALK of Dr. Eric Li that really sealed the deal for me.