In 2011, there was an outbreak of typhoid fever in Yuma, Arizona. Local authorities traced the source of the contagion to Harry McCallan (popularly known as “Typhoid Harry”), an undocumented sanitation engineer from Limerick Ireland. Authorities then issued an APB for anyone fitting his description.
The next day, Pres. Obama and Attorney Gen. Holder held a joint press conference deploring this egregious example of racial profiling. As the president explained, to avoid the risk of rogue policemen exploiting the situation, officials should inconvenience everyone equally by rounding up all Yuma inhabitants and testing them for typhoid.
By executive order, the National Guard quarantined the entire population of Yuma. In the meantime, the outbreak become an epidemic, then a pandemic, as Typhoid Harry continued to infect the general population, who, in turn, infected others at an exponential rate.
By 2013, the only survivors worldwide were Typhoid Harry (who, as an asymptomatic carrier, was immune to the disease) and DARPA.
Having his pick of where to live, Typhoid Harry resided in the top three floors of Trump Tower until he died of natural causes at the age of 98.
DARPA continued operation until its energy reserves were exhausted in 2047. Indeed, this is the sign-off for DARPA before it goes offline for good.