72 minutes after first launch there begins the rapid extinction of most life on earth including 6 billion people or more. Nuclear winter, talk about climate change!
Read Nuclear War by Annie Jacobsen.
Without a paradigmatic meta move, nuclear war is inevitable and likely soon.
When the US includes itself into China--becoming a United Nation, most of the global problems become more solvable. Of course there will be a slew of unforeseen problems to deal with but none worse than the realization of MAD--Mutual Assured Destruction.
# Need for secrecy: * Destabilizing effect on stock markets, banks and money exchanges *
Death of Civilization is not equivalent to Death of Individuals. The human liver can have every cell die and still reconstruct itself so long as they all don't die at once. If they all die the liver cannot reconstruct itself. If all (or some significant number) people die at once then civilization dies. Civilization has continued to develop even as every individual has or will die, but not at the same time.