The Chinese are welcomed by leaders because they shovel money directly into the bank accounts of those leaders without hesitation or restriction. The Chinese are rapidly making themselves as hated as westerners in much of the world, largely due to bribery (always hated by those who don't get the bribes) and racism.
What I hear from the Vietnamese is that the Russians were arrogant, condescending, racist, and epically malodorous. Their help was accepted only because it was needed and there was nowhere else to get it, and relations broke down quickly once the help was no longer required.
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