POD usually includes an ongoing series of dialogues on a wide variety of alternate history and related topics.  In some cases those threads are incomprehensible without reading the last several issues of POD.  In other cases they are quite a bit of fun--an ongoing brainstorming session where I generate a lot of my best AH ideas.  As in most brainstorming sessions, the comments are off-the-cuff and without a lot of rigorous fact-checking, but you may find them interesting.

 On professional versus amateur cons: It's interesting how having professionals run things somehow results in a lot of the fun going away. At the same time, even from my limited exposure to science fiction cons I can sense that they vary a lot in how fan-driven they are. I suspect that it's easy for commercialism to creep in and for a con to become more about making deals than about enjoying oneself, especially as the con gets bigger.

On over-flight rights for satellites The bit about the 
Soviets establishing the right of orbital over-flights with Sputnik is very interesting. If we had been first to orbit, or if the Soviets had thought through the implications a little more thoroughly we might have seen a very different Cold War. I'm reasonably sure we would have still put up spy satellites. Would the Soviets have tried to develop weapons to knock them down if they went over Soviet territory? Would they have turned up the heat diplomatically? Maybe. On the other hand, extending national sovereignty into orbit gets really unwieldy in a hurry, and it makes a lot of things that benefit everybody impossible. 

If the Soviets did manage to shut down orbital spying though, things could have gotten really ugly any number of times during the Cold War. We would have probably developed a force structure for the worst case Soviet power—maybe ten thousand Minutemen (as was proposed at one time), a thousand of so B70 bombers, anti-missile defenses with those ever-so-practical explode over your own territory warheads, and maybe something like the Dynosaur (not all bad I guess, assuming we didn't blunder into a nuclear war).

On the Korean War and lost technology: By the way, I discovered not long ago that one of my uncles actually worked on the B70. He wasn't a designer or anything, just a middle-level tech guy. We hadn't really talked that much over the years, but since his son died about a year ago we've been getting a lot closer. He has had a very interesting life. Unfortunately, he also has inoperable prostate cancer. The guy fought in the Korean War, and had some very interesting stories about that experience, including one where he was sent out to map out a mine field and discovered after he had crossed it that the mine detector he had been given wasn't working. Not something that gave him a lot of confidence in his commander. He also had some weird stories like the time his company bugler was goofing around with a captured Chinese signal horn and accidentally sent the signal for the Chinese to attack, which they did. Fortunately the Chinese weren't really in position to attack at the time so it actually ended up working out okay from a US perspective. 

Then there was the time shortly after the war when a Korean civilian helping move ammunition accidentally pulled the pen on a grenade. He didn't quite what to do with the grenade, so he just stuck it back in the box with the other grenades, which was on a truck with a whole lot of other boxes of grenades, which was parked by a whole bunch of other trucks filled with ordinance… Of course the bit about the accidentally pulled pin is probably just a guess. Nobody within visual range survived the resulting fireworks.

My uncle has an interesting perspective on technology. His company was a major subcontractor for most of the major space projects. He claims—probably rightly—that an awful lot of the knowledge on how to actually make things work exists only out on the shop floor. In other words, a lot of the knowledge necessary to actually make the likes of a Saturn 5 existed only among the machinists and test technicians of the various subcontractors that made it. The company he worked for routinely bought machine tools that were not good enough to do the very demanding precision work that they needed to do, then rebuilt them so that they could actually do the job. 

I suspect that my uncle and people like him have little bits of knowledge kicking around in their heads that people would pay an almost unlimited amount for once they realize that it is gone. Of course current attitudes toward the accomplishments of the Apollo program seem very cavalier. I read online a while back that a researcher tried to find the computer programs that calculated the trajectories to the moon for the Apollo flights, only to discover that the punch-cards had been thrown away a few months before. If true, that's very unfortunate from a historical standpoint.

It is kind of a weird concept, but even in the modern world industrial processes can get lost. How would you build the belt armor or main guns for a battleship if for some reason you wanted to build an exact replica of a World War II battleship or a modern equivalent? I honestly don't think that even a great power could do it without a huge decade-long effort. Too much of the down-to-earth little techniques have been lost. The huge specialized furnaces don't exist anymore. The tooling doesn't exist anymore. The machine tools are gone and the people who knew how to use them are dead.

A few years ago some guys in Germany ran into these same problems on a smaller and more manageable scale when they set out to built some replicas of the FW-190 World War II fighter plane. Last I heard, they apparently had figured out how to do it, but they had to go to some of the most backward parts of the former east bloc to find people who still understood some of the manufacturing techniques.

Why are there few cold country monkeys?  I did quite a bit of thinking about this while I was plotting "Bear Country". I suspect that you'll find that there are simply limits to how cold a climate a large non-hibernating omnivore is going to be able to make it through. It's just a matter of food supply. 

Having my little green monkeys in Illinois is really pushing it about as far as I comfortably could. At the same time (a) In Asia there actually are quite a few cold weather monkey species—not ones capable of making it through a Siberian winter, but ones that range as far north in climate terms as say North Carolina or Virginia. (b) Europe had a wide range of primates as late as the Pliocene, but as ice ages developed, each one left fewer surviving species. They got pushed back into cul-de-sacs in Spain, Italy, and the Balkans. All it took was one period at the coldest point of an ice age and they were gone.  Once the last of the European primates died off, there was no easy way for primates to get back into Europe during the interglacials without human intervention. A forest or savannah corridor would have to develop around the eastern Mediterranean or from some area in Asia with primates. (c) Baboons are tough. I've heard of them wandering around in the snow at Moscow zoos during the winter, and surviving in climates so dry that they have to work to conserve every drop of water. 

In North America, there has been a limited time for the monkeys in Central America to move north, and a lot of that time has been during ice ages. I suspect that given a few more million years, especially without ice ages, moderately cold country species would develop. One of the problems is that South American monkey species are very arboreal, probably because less arboreal ones would have been very vulnerable to the more advanced predators that flooded in about a million years ago. That makes any treeless corridor a major problem. Advancing from a relatively primitive predator area to a more advanced predator area is going to be difficult.  On the other hand opossums did it, so it isn't impossible.

On the Colorado River and agriculture, Colorado River Indians domesticated a couple of local water weeds after they started growing corn. I don't know how much crop potential the local stuff had.  Would it eventually have supported an agricultural civilization even without corn?