Today, we continue to witness the same scene, with all the colonial powers able to take advantage of the crisis by selling weapons to all parties and fueling more religious and sectarian conflicts, turning the entire region into a weapons testing Lab. Is it in the interest of these peoples to devote all their resources to arming themselves to kill each other? As Pooya said, find the beneficiary and you will understand exactly what happened and what is still happening.
This argument is similar to the men who blame the devil for their sins. Each country is responsible for their own actions and decisions. If there are two countries at war among themselves, it's because they decided to do so, and not because there is a third country selling weapons to them.
To blame USA for every problems people face in their own countries just remove the focus from the root of the real issues while sounding like an envious and resentmented statement. Probably the first step for third world countries to overcome being third world countries would be to stop blaming USA for their own inability of addressing local issues and diplomatic questions.
These statements are all based on facts and historical events including the interventions of Western powers to destabilize the region. Not just empty accusations to remove the responsibility on these countries.
In my opinion the best example that would help anyone understand these facts and see things more clearly is Syria. Just spend a couple of weeks studying the history of the past 2-3 decades of what happened in Syria. There are lots of similarities. You will even find similar arguments where people say "you are blaming the West for no reason".
10-20 years ago when we were saying it is US that is waging a dirty war against Syria, attacking people with chemical weapons, supporting terrorist organizations including but not limited to al-Qaeda and ISIS, etc. nobody believed it. Most people wanted to repeat the US propaganda that "Assad is dictator", "it was Assad that carried out the chemical attack against his people", "the ISIS terrorists are just protesters", etc.
Today Assad is gone and Syria is under occupation of various terrorist groups (al-Qaeda occupies the capital and a couple of other provinces, Israel occupies western regions and Golan heights and main water sources, ISIS occupies a handful of provinces, various little terrorist groups that call themselves Kurd occupy eastern parts of Syria).
This means you can find the truth easier...
Syria is not the only example. Throughout modern history, the vast majority of civil and regional conflicts are externally manipulated. The parties that benefit from these ongoing conflicts are the ones operating behind the scenes. India and Pakistan are one people with a common culture and history. How did this hostility develop between the people of the same country? Colonial powers fueled these hostile sentiments and kept them boiling to exploit them whenever necessary.