You wouldn't need to provide much evidence to convince someone that the US certainly makes a great excuse or scapegoat. However, to simply state the US involvement in the Middle East is the reason ISIS and similar groups have flourished doesn't merely strain credulity, it ignores practically a millennium of history, extremely complex political, social, cultural and religious dynamics, and not to mention US support for Israel and funding of the Saudi regime is at an all-time low, and at least as much if not more weapons came from USSR/Russia than the USA. So I assume you're just trolling.

The reality, I believe, is much closer to the same reason it always comes down to when men commit acts of brutality in order to subjugate or terrorize a population. They do it because of ego, pride, opportunity, and a desire for establishing their own power, not because someone else made them do it or in seeking justice in face of tyranny.

If anything, I think it's more likely the premature US withdraw from the Middle East and a lack of stronger support for Israel which has contributed to ISIS flourishing. A perceived faltering of support between two allies is the best invitation for increased pressure and targeted attacks (physical, political, clandestine, and otherwise) against the bonds between those allies. It doesn't surprise me at all that countries and religious fanatics with the stated goal of the destruction of Israel would work tirelessly to popularize the notion that if only not for the US "supporting Israel" the Middle East would somehow be more stable.

Mostly I pin the blame for the flourishing of ISIS collectively on the Middle Eastern countries which themselves have epically failed to confront the rising threat of ISIS on their own turf, while doing seemingly everything possible in their own domestic policies to in fact encourage ISIS recruitment. Assad'd deployment of chemical weapons is mirrored in Egypt's own treatment of citizens in Sinai, and over and over again throughout the Middle East, we see effectively a ceaseless and brutal civil war stretching back, what, 1400 years, only interrupted by periods of apparent calm when one tyrant or another manages to temporarily cement themselves so far above reproach that their own raping and plundering goes uncontested for a relatively short while.

The Middle East has been facing endemic war between Islamic sects basically for the entire history of Islam itself. The "holy wars" (call it barbarism or medievalism) being carried out in the name of Islam (by so-called "Islamic terrorists") is evidence enough that this is not actually problem of foreign policy, but a deep seated and historically pervasive domestic problem.

The inescapable "defunding" of the Middle East over the next few decades is unsurprisingly leading to a surge of sound and fury, signifying little, and ultimately will disappear in a whimper. These are countries which by and large by their own actions and circumstances have squandered a most incredible glut of natural resources (as is human nature) and as that era comes to a close in relatively short order, will bring with it a humanitarian crisis throughout the region, which frankly, neither the US or any other World power, is either responsible for, nor has the political will, nor even the available resources, systems, or infrastructure to adequately address.

The massacre in France is abhorrently evil and sensationally shocking. Statistically, it is a drop in the bucket. I can't even comprehend, for example, the scale of horror and violence which is being inflicted daily against disenfranchised Muslim women and girls who are married into bondage, raped, and brutalized, as a token reward / enticement for ISIS recruits, even wrapping this torture in a veil of propriety and calling it Sharia.... A sickness like that, to me, can only be understood, explained, spread, and ultimately eradicated domestically.