The basic idea that there was some kind of limit on how many wars the U.S. could fight in a region in a certain time frame. I semi-randomly set the cap at three and suggested the US was over it: Iraq, Afghanistan, Libya plus war-ish activities in Pakistan, Yemen, and Somalia. I thought that the US would be free to launch a new war in 2015 when Iraq rolled off of the cap. But if the US goes back to Iraq, does that count against the cap or is it just the continuation of a war that is already "under contract"? In the NBA, there are exceptions for signing your own super-star players (the Larry Bird rule). So, I guess that going back to Iraq is covered under the Larry Bird equivalent... which would be ...the Douglas MacArthur rule?
On the other hand, Syria would be a new war for the U.S. and would definitely put over the war cap. The question then is: what are the penalties for exceeding the cap? Ask the soldiers who do the fighting and the budget analysts about the long term costs.
Of course, my larger point that all this silliness may either express or cover up is that the US has fought quite a lot in the same area over the past fourteen years, and that has many consequences. Exhaustion, reduced legitimacy, financial costs (estimated at more than three or four trillion dollars to be spent over the next eighty years or so--not unlike the uncapped NY Yankees), and so on. So much war has also taught us something (or it should have): humility. The use of force is quite good at breaking stuff, but building political stability? That the U.S. with and without allies has used varying levels of force from all (Iraq, Afghanistan) to some (Libya, Pakistan, Somalia, Yemen) to none (Syria) and the only thing that is consistent are the results.... lousy.
Maybe the U.S. is the Yankees of IR--recklessly spending, learning few lessons, and nostalgic for championships long ago .*
* The Yankees won in 2009? Who remembers that? Other than wikipedia?