I think our involvement in the Middle East since WWII has certainly destabilized the political dynamics of that part of the world but let's not forget why the Middle East became so important in the first place....the discovery of oil and the ever increasing demand of said resource by the rest of the world.
But even before the world sought to control this important resource Islam has been a source of instability to both the countries in the region and those outside of the region. The sectarian war between the Shias and the Sunnis has been going on for centuries and when they weren't at each others' throats they were attacking other countires. In fact if not for the Franks defeating the Muslims(Moors) at the Battle of Tours, Europe may well have fallen under the sway of Islam. Thank God(literally) for the Franks.
https://en.wikipedia.org/wiki/Battle_of_Tours
The point being, Islam is not the religion that stable societies are built on. If the US and the West had not initiated the current unrest with the overthrow of Mossadeq and continuing until the current Iraq/ISIS disaster there would have been some other country or incident that started this whole mess into motion because that's just how Islam rolls which means the region and the countries under the influence of that religion will always be a tinder box.
Personally, I would prefer the US stay out of that quagmire as much as possible and let the ancient shiekdoms fight it out to the death among themselves.