Many countries attempted to deal independently with the aliens. In August 1998, Japan established an anti-alien combat force; the Kiryu-Kai. Equipped with advanced fighter aircraft, the Kiryu-Kai looked like a powerful force. However, after 5 months of expensive operations they had yet to successfully intercept their first UFO. The lesson was clear: this was a worldwide problem that could not be dealt with by individual countries.
On December 11, 1998, representatives from the worlds
most economically powerful countries gathered secretly in Geneva. After much
debate, the decision was made to establish a covert independent body to combat,
investigate and defeat the alien threat. This organization would be equipped
with the worlds finest pilots, soldiers, scientists and engineers, working
together as one multi-national force. Officially, this organization was named
UNETCO.
Or just: XCOM.