The Interim Years | 2001 - 2004
They called it the Black Mesa Incident: The actions of this facility had caused an extra-dimensional event which had destabilized the very functioning of space and time to the point of no return, allowing flora and fauna from Earth and the borderworld of Xen to freely cross over with ease. Entire cities were overrun by alien creatures, and South American countries like Brazil and Colombia had reported some sort of intelligent alien life invading from the heart of the Amazon Rainforest, attacking isolated towns and besieging cities alike. In America, the epicenter of the Black Mesa Incident, things were worse than ever. The American southwest had become a nuclear wasteland, destroyed by the U.S. military's attempt to destroy the portals and surrounding alien threats. Cities like Albuquerque and Las Vegas had become irradiated husks, their inhabitants destroyed by atomic hellfire. It only slowed the advance of the alien onslaught however: Antlions, Gonarchs, and all other manner of alien creatures were steadily pushing back the military defensive efforts, and it soon became clear that there was little chance they would be able to eradicate the foreign creatures in any short war. By 2002, not only America but the rest of the world had set up massive safezones, defended by what little soldiers they had left. Cities like Los Angeles and New York were guarded by massive walls, checkpoints, and razor-wire fences, alongside a sizable contingent of soldiers to maintain order. These safe zones became something like massive ghettos: All manner of poverty could be seen here, with some people killing others over something as simple as a bottle of water. It was so bad that many fled these safe zones to make it out in the ruins of the world. Many didn’t last more than a few weeks.
A portal storm erupting off the shores of Norway. Note the low-altitude causing the storm to consume the ocean
Europe had suffered the least from the Black Mesa Incident, with small portal storms consuming many sparsely populated sections of Northern Europe and Russia, but with a majority of their population and agricultural centers intact. Millions fled by land, sea, or air to get to Europe, whom more often than not turned these refugees away due to the already dire situation with their own population to worry about. A massive migrant crisis followed, with roving bands of foreigners often attacking anyone for food and equipment that could help them survive. The instability and lack of safety also had caused Europe to retreat in on itself, with metropolitan areas becoming more densely packed than ever.
By 2004, the world population had shrunk by 2 billion souls. South America was largely consumed by alien invaders, with only small holdouts remaining to oppose them. The United States was battling an endless war between itself and the Xenian scourge, obliterating it’s heartland with nuclear warheads. Europe struggled to stay afloat battling the alien threat and their fellow man at once, and places like China, Japan, and so on had largely went completely dark, with communications from the outside world being cut by 2002 or so.