This has already happened at least once.
There's reason to believe that the Anasazi are somehow related to the Japanese. There are some quirks of blood factors and language structure that set this tribe, and their modern descendants the Pueblo and the Hopi, apart from the usual run of feather niggers.
Up until the 12th century, they lived in open-plan cities all over the Four Corners region. We know there was a vast network of roads connecting the towns, and that they practiced large-scale agriculture within irrigation range of the rivers in the region. Life was okay for them.
Then, in the 12th and 13th centuries, the climate shifted. Just as Europe was shuddering under torrential rains and a suddenly cooling climate, the Southwest was drying out and getting hotter. This wasn't an emergency at first, just stressful. The Anasazi had a well-buffered civilization, after all. What could possibly hurt them?
Conditions were worse in the valley of Mexico. Years of bad drought all but annihilated the savage civilization of the Toltecs, Mexico's first pyramid builders. Some of them went south in the collapse, where they influenced Mayan culture, while the ones who stayed were seen by the Aztecs as ancestors. Those who went north, however. . .
Starting around 1200 AD, the Anasazi abandoned their open cities and relocated to cliffside pueblos. The flat-land cities all suddenly started building high walls and guard towers. The roads fell into disrepair, suggesting the decline of trade and unified tax revenue. Strangely, the population kept rising in the region, which is the opposite of what you'd think would happen in a civilizational decline. At the same time, there's evidence of boiled childrens' bones and cannibalism in the ruins. This is "controversial," because the Pueblo get really touchy and butt-mad if you suggest their ancestors weren't noble philosopher kings, but the bones are of children, and they have been boiled and scraped for meat.
Eventually, what remained of the Anasazi fell apart entirely. Even the name we use for them comes from Navajo (not an Anasazi tribe), and it means "ancient enemies."
It seems clear what happened. Changing climate and the basic fucked-uppedness of Mexico drove out the idiotic savages living in its central valley. When the Toltec savages got to the Four Corners region, the Anasazi tried not to be racist and accepted their equals as refugees. Tens of thousands more followed, and probably they all had an r-selected birthrate, like the filthy fucking termites they are, and when there were enough of them they probably stopped even trying to learn the Anasazi language or abide by their hosts' customs. In came the human sacrifice and cannibalism, out went the tax revenue, down went the roads, and up went the banners of war. Then, after everything collapsed, the survivors straggled out into the desert as new tribes who gradually lost even the memory of the Anasazi.
Mexico is a biological weapons factory. It is a sewer, and in the best of times the rats are happy to stay there. Let it flood, on the other hand, and they know right where to go for free food and a place to drop their eggs. I fucking hate Mexicans so fucking much I could scream.
Attached: Aztec_Childcare.jpg (250x188, 18.11K)