To satisfy condition 1, we need to put an idiot in the White House. The military as its constituted now won't let a war of attrition occur. We need a very liberal President of the United States who deeply slashes defense spending after prematurely declaring victory in some conflict. This president emerged from the Vietnam Anti-war movement, and he deeply believes that War is not the answer no matter what. Of course some dictators catch wind of this and they begin rattling their sabers and threatening war unless the US grants some concessions to avoid war, this the US does because the President believes War is not the Answer and for a time he does this successfully. We should give Dictator "Uno" about 10 to 15 years to build his empire. The U.S. carefully avoids tangling with dictator "Uno" because he detests war but is otherwise a successful president, after serving two terms in office, his vice-president is elected president for another two terms.
Meanwhile Dictator "Uno" is a very efficient and ruthless leader who executes all his opponents and rapidly industrializes his once poor country. Everyone gets a job, men get drafted in the Army. Dictator "Uno's" country conquers a number of surrounding countries using "revolutionary" tactics of subversion rather than open confrontation. The U.S. President lets him get away with this, and the countries neighnoring Uno's, but not bordering it, are also run by pacifist liberals who want to avoid provoking Uno into conflict. Finally Uno's armies run into a country that's not willing to give in without a fight. The U.S. President is unable to look the other way this time without being made to be seen a fool by his political opponents and so tries to makeup for 15 years of military neglect in his last year in office. The result is World War III.
This is basically the same scenario that started World War II. Dictator "Uno" in that case was Hitler. In this case perhaps "Uno" wears a towel on his head and grows a beard, or perhaps "Uno" is Chinese. No doubt a Chinese "Uno" would want to get a hold of Taiwan and a few other places. "Uno" might be Japanese. Perhaps Uno's country is a combination of Japan and China, with a United Korea thrown in. A country made up of those four countries could present a serious challenge to the United States. The Communist backwardness is completely tossed out of China. The Chinese adopt a completely new nondemocratic form of government with unfettered capitalistic mechanisms inside the country while cross-border trade is regulated. This government is completely ruthless in eliminating people who prove to be a burden on the government. In another era this government might be described as "national socialistic" or facist. The weak and the crippled are eliminated as are people described as inferior races. Of course the Mandarin Oriental is the "Master Race" in this case and all others are considered to varing degrees as inferior.
This country does not exist, so that's why it needs 15 years to form, and 15 years to reach the point where it believes it can conquer the world. Both sides have done active research in missile defenses, and they are roughly 99.9% effective, but the remaining 0.01% of the missiles that get through wrecks a lot of havoc and society breaks down. Many cities are spared destruction including NYC, but the residents of those cities flee in panic as the missiles fly. Work does not get done because people refuse to return to those cities where the work is. Enough cities are destroyed to cause a panic but not much beyond that.
