Colonialism is a nice, convenient way of blaming anyone and everyone but oneself. Furthermore, it doesn't explain a damn thing with respect to the absolute barbarism we see in many parts of the Islamic world with respect to women, with respect to "apostasy" and free thought, with respect to religious tolerance or with respect to the casual violence that seems to be eating away at that part of the world like a cancer. Let's look at the colonial histories of Muslim nations:

Saudi Arabia - an Ottoman (Muslim) colony only
Yemen - only Aden was ever colonized
Turkey - never colonized
Iran - never colonized (Shah did come to power with Western help, but that was it)
Afghanistan - failed attempts at control on the part of the British

Yes, Pakistan was a colony, but its aberrant nature today is far more of a result of its post-colonial "ethnic cleansing" of anyone who thought differently (Sikhs, Hindus, Christians, Buddhists, Jains).

Yes, Syria was a colony, but it is being torn apart along sectarian lines, just like neighboring Iraq, and it is sectarian conflict that tore apart Lebanon in the past and threatens to again now, not some "colonial past".

In fact, it's clear that in almost every case, the nature of present disruptions have to do with Salafist or Wahhabi movements or religious disputes between Shia and Sunni.

Where do these apologetics stop? Seriously, the problem is not one of our making, by and large. It may be aggravated by certain policies that we've had, from support of Israel to the invasion of Iraq, but the problems would be there even without those points because the simple fact is that most Muslims are intolerant, and a significant number of them are violently so. They find direct support for this stance in the Salafist reading of the Qur'an.