Quantum computers are already here in a limited form, and fully functional versions are on the way. They will be as transformative for mankind as were the mainframe computers, personal computers, and smartphones that we all use. As do all advancing technologies, they will also create new nightmares. The most worrisome development will be in cryptography.
If the first 15 years of the 21st century were defined by the so-called Axis of Evil -- the phrase George W. Bush applied to Iraq, Iran, and North Korea for their support of terrorists -- the next 15 years will likely be defined by the Access of Evil, as state and non-state cyberterrorists use technology to bypass our defenses in ways that damage businesses, lives, and nations.