NK has 8000 artillery tubes and 2500 artillery rockets to use up.I have already stated that they can do great damage to Seoul. But Seoul isn't the entire country. An artillery piece has a limited range. Even the long range ones peak out at about 20 miles.
Even running around the clock it would take all the air forces you mentioned, combined, a long, long time to even find all of NK's artillery sitesThey are in fixed sites. Once the gun fires, radar picks up the shell in flight. The gun is found and marked. Many of their places are already known, but I have no idea how many.
. ...let alone destroy them. Once the tubes are found the attackers air-force has to fly over NK airspace then back around toward the south to have a good run at a target.To be able to hit very far into the South, an NK arty piece will have to be pretty close to the DMZ. So we are talking about a trip North of a couple of miles, a turn South, and pickle the bomb. Not a big deal.
To insure accuracy, these runs will probably have to be made at low to medium altitudes.VERY WRONG!!!! You are thinking of WWII bombing runs. Even at the close of Vietnam we were using laser guided bombs. Now we use GPS guidance, and they can have the targeting data loaded into the bomb while the plane is in flight. GPS guided bombs are just as accurate dropped from high altitude.
Now the attacking air-force is open to NK's massive, yet antiquated, air-defense system.Nope. For reason above, and because we will be working on that air defense system. Every time they light up a radar, it will have an anti-radar homing missile coming at the radar, or it will be jammed, or spoofed.
So what you will have in the first days, if not weeks, of a conflict is the attackers air-force concentrating on NK's air defenses.Nope. With GPS guidance on the bombs, we are able to be so accurate that we can use a smaller bomb than before to get the same destruction where we want it. That means the plane can carry more bombs, each one ASSIGNED TO A DIFFERENT TARGET. One plane can take out over a dozen artillery sites.
All the while NK's artillery will be hammering the south with ground troops pouring through the DMZ under the cover of said artillery.The tactical answer to that is well known. We would have to fall back a few miles from the DMZ. That would be part of any competent military's plan. It is like a boxer who rolls with the punch. This puts their infantry forward of the coverage of their artillery. Then they have to move the arty, and it is much easier to take out once it starts moving.
Also, by dropping back you force them to reveal the axis of their attack. They have to move supplies forward and air will be chewing up those supplies.
Those troops will be in the open and will be chewed up by our MODERN artillery, cluster bombs, fuel-air bombs. They will be counter-attacked by modern, well trained, highly mobile forces. That infantry will be tank and cannon fodder.
The combined forces of the US, SK and maybe Japan could eventually prevail but the cost would be incalculable.The cost would indeed by high, but it would be even higher for NK, and he can't afford any cost.
You seriously do not understand how extremely expensive it is to keep a military well trained, nor do you seem to understand the value of training. To train a mechanized army requires getting some time in driving the equipment around and that isn't cheap. Pilots have to fly and practice dogfighting. NK pilots get only about 30% of the flight time SK pilots get. And we also have great simulators that they just don't have. The bulk of their forces are poorly trained. Further, they are trained in the old Soviet model. Each troop know his job only with very little cross-training and NO expectation of initiative.
Let's take a look at some of the equipment balance.
http://www.democraticunderground.com/discuss/duboard.php?az=post&forum=102&topic_id=2565646&mesg_id=2566354 Tanks are a major tools for a modern army. NK's most modern tank is the Type-59 which first appeared in 1964. (500 available) T-62 (1962 model, 800 on hand)T-54 (1954 model 1,600 on hand), T-34 (WWII model 250 on hand), PT-76 (Lightly armored amphibious tank. Basically useless. 550 on hand) Total of 3,500 obsolete to very obsolete to museum piece tanks). None of those have shoot-while-moving ability. To accurately fire the main gun the tank has to come to a complete stop, then the gun has to be aimed. Sights are optical reticle-range type.
Now let's look at SK tanks. Type88/K1A1 - These are a clone of the US M1A1. An extremely modern tank, thermal imaging sights, laser rangefinders, fire control computers. It has to ability for the crew to acquire a target, aim and accurately fire the main gun while on the move. From seeing the enemy target the crew can have a precision aimed round on the way in less than ten seconds - without having to stop the tank. (1,000 on hand)M-47 400 on hand. Older tank, about equal to a T-62. T-48 850 on hand, Introduced in 1954.
Very little is know about other NK systems, but it would be reasonable to conclude that they would be in a similar state of obsolescence.