In the last few years, nuclear war and nuclear weapons has taken somewhat of a back seat to more conventional forms of killing (AK-47s, tanks, etc.) and even to the mega-simple (IEDs), but earlier this month the annual meeting of the American Association for the Advancement of Science opened up the old Cold War can of whup-ass.
Discussions at the gathering revealed what even a small, contained nuclear exchange between neighboring countries could do to the globe’s environment, and if you figured global warming/climate change was some bad shit, then just wait…
From Wired‘s coverage of the event:

“This is tremendously dangerous,” said environmental scientist Alan Robock of Rutgers University, one of the climate scientists presenting at the meeting. “The climate change would be unprecedented in human history, and you can imagine the world … would just shut down.”

And in an interview with Michael Mills, an atmospheric chemist at the National Center for Atmospheric Research, some real-ugly stuff.

Wired: In your simulation, a war between India and Pakistan breaks out. Each country launches 50 nukes at their opponent’s cities. What happens after the first bomb goes off?
Mills: The initial explosions ignite fires in the cities, and those fires would build up for hours.
What you eventually get is a firestorm, something on the level we saw in World War II in cities like Dresden, in Tokyo, Hiroshima and so on.
Today we have larger cities than we did then — mega cities.
And using 100 weapons on these different mega cities, like those in India and Pakistan, would cause these firestorms to build on themselves.
They would create their own weather and start sucking air through bottom.
People and objects would be sucked into buildings from the winds, basically burning everything in the city. It’ll burn concrete, the temperatures get so hot.
It converts mega cities into black carbon smoke.

And after explanations of some rather ugly scientific shit:

Wired: What would all of this do to the planet, to civilization?
Mills: UV has big impacts on whole ecosystems.
Plant height reduction, decreased shoot mass, reduction in foliage area.
It can affect genetic stability of plants, increase susceptibility to attacks by insects and pathogens, and so on.
It changes the whole competitive balance of plants and nutrients, and it can affect processes from which plants get their nitrogen.
Then there’s marine life, which depends heavily on phytoplankton.
Phytoplankton are essential; they live in top layer of the ocean and they’re the plants of the ocean.
They can go a little lower in the ocean if there’s UV, but then they can’t get as much sunlight and produce as much energy.
As soon as you cut off plants in the ocean, the animals would die pretty quickly.
You also get damage to larval development and reproduction in fish, shrimp, crabs and other animals. Amphibians are also very susceptible to UV.
A 16 percent ozone depletion could result in a 5 percent loss in phytoplankton, which could result in a 7 percent loss in fisheries and aquaculture.
And in our model we see a much greater global average loss of ozone for many years; the global average hides a lot.
Wired: This doesn’t sound very good at all.
Mills: No, as we said it’s a real bummer.
It’s pretty clear this would lead to a global nuclear famine.

As a baby boomer, I’m fairly well-acquainted with the nuclear threat — all the propaganda-induced fear rolled like a nasty, salty tide across the 1950s and early ’60s.
One in an incredibly-long list of horrifying things mankind has done over the years was to break-up the atom — there can/will be no peaceable result from either nuclear power (as in electricity, energy) and nuclear weapons (nuclear war) as waste from both products are mega-mega harmful.
The current US nuclear-plant/storage of eons-long-dangerous-spent-fuel situation is beyond hideous — The total quantity of spent fuel stored at U.S. nuclear reactors in 2002 was 47 thousand tons. An additional 20 tons of spent fuel discharged per year from 104 reactors for 9 years totals 18.7 thousand tons, so our estimate is that the total quantity of spent nuclear fuel currently stored at U.S. reactors exceeds 60 thousand tons (from the NRDC).
And spent nuclear fuel is bad beyond imagination.
No real good has come from splitting the atom.

Especially, the most obvious via warfare.
In the tone of the Wired story, National Geographic in a piece last week reported this small nuclear-weapon exchange would indeed reverse global warming, and could be even worse than the awesome catastrophe now coming under the current warming-up scenario — great global cooling: Earth is currently in a long-term warming trend. After a regional nuclear war, though, average global temperatures would drop by 2.25 degrees F (1.25 degrees C) for two to three years afterward, the models suggest…For a time Earth would likely be a colder, hungrier planet.

And the global civilization created in less than two centuries, could go in a pop-of-a-second.