The pre-war for the Middle Eastern Conflict was Desert Storm, which in Shifters Universe occurred in 1988-1989. The mega city projects however, was already in development at that time, although not to full scale. Three years later in 1992, a secret agreement was signed by the president to absorb 1 nuclear strike and not 'fire on warning'. Two years later, in 1994, there was a nuclear explosion detonated in the air above Denver, Colorado. The nuke itself was devastating, killing millions, spreading radiation far and wide, carried by the winds and poisoning much of America's prime farmland even as far away as Kentucky. But the real nasty piece of work, which went largely unnoticed in the wake of the bomb, was the plague that was released at about the same time, quietly, mostly through the central and eastern states. It wasn't until about 1993 that it began to show up on people's radars. The incubation period of about 11 months ended and people east of Nevada began to drop like flies (those that hadn't already died due to radiation or starvation). The mega city plan had moved forward for the last 8 years or so in the western cities ( Shade City, centered on where Seattle stands today) and Pacifica (Centered on Los Angeles and surrounding areas)
The west had been spared much of the initial exposure, although travelers who'd been in the east in the 11 months prior had brought it back with them. The mega city areas enacted quarantine procedures and controlled the diseases relatively quickly within their respective borders which began a certain isolationist culture within both Pacifica and Shade City, however, refugees were demanding entry to the west and eastern megacities, which prompted accelerated growth of all four mega city projects and the addition of two more in the east. The plague decimated the population, particularly in the central to eastern US over the next five years.
A terrorist group from the Middle East claimed responsibility for the attack, however the US discovered that it was covertly backed by a small group of Middle Eastern countries in response to the earlier war's atrocities. The US government was given permission to 'go after' the terrorist group in question and anyone who harbored them. this became the war known as Middle Eastern Conflict, and was considered to have lasted from 1996 - 2005. However, because of the waning power of the US, budgetary issues, domestic civil unrest, environmental and food crisises on the homefront, they were forced to withdraw their main forces. The conflict in the Middle east continues, but is limited to smaller strategically deployed teams and technology based units.
In the time the government was busy, the corporations seized the opportunity to woo many changes to laws to be favorable to them to run many programs and control a lot of civil life in the name of safety and well being of the citizens, saving the government money, and putting themselves in positions of absolute power over the cities they funded. As a result, currently, the Mega Cities are more like corporation states, where the government is there more as token than law of any sort. The corporations can pretty much do whatever they want to with the citizens who live and work in the Mega Cities that they want. Military service does guarantee one can get access to a Megacity home (this is not always the case for all 'immigrants'), although its often not in the nicest areas, but they get a place to live, and a meal/pension for their service, as well as job opportunities through the corps. This is part of the deal the corps have with the governments.
I've included a map to show the general state of things in current time.
To really know a normal life, a character would have to be probably about 45 years old.
