The second quote is by some wingnut commenter on Slate who later goes on to cite frontpagemag, not by Fred Kaplan.

On the first, I'll note that there were two events: an order by Clark to occupy the airport in advance of the Russians, and a later order by Clark to block the runways with tanks. Both were refused by Jackson. Russian air lifts were eventually held back by the US convincing the surrounding states to close their airspace. It's unclear to me where exactly the 'World War 3' quote comes in as the BBC gives a different picture.