1. Hill tribes, be it Nepalese or NE Indian, have a cultural disdain for plainspeople. They see themselves as superior, martial race and plainspeople as weak. Speaking from experience, a cultural subtext in hill cultures often are that Hill people are sons of the soil, uncomplicated, trusting people while those from plains are evil, conniving bastards swindling and exploiting the simplistic hill folks. That is the mindset they gave grown up with. When confronted with the reality that the mighty and martial Nepalese nation is much less powerful than a plainspeople nation, there's hate.
2. Does Mexico, Panama etc love America? They do hate and blame America for their troubles. But Mexicans and other South Americans do love coming to America and earning, the benefits it bring all the while disliking America. USA is the biggest power broker in their region and exerts control and influence. When you can't compete, you hate.