Its the almighty law of action and reaction.
The USA and most EU countries had their way with the 3rd world for decades, countries like Iran, Iraq, Lybia, Egypt, Tunisia, Ex-Yugoslavia were all doing pretty well 20-30 years ago. Former colonies that managed to free themselves from colonial slave masters and form the "non-aligned nations" and prosper for themselves.
Then came the US foreign policy, decades of economic sanctions, oil theft, bullshit politics and viola! you have broke regions in the world spilling their problem in to your countries now. Had you not bombed, economic sanctioned, isolated, corrupted and exploited their countries to shit they would have viable economies and normal leaders today and would not come over in droves.
The UN has its hands dirty here as well. The systematic rape of the 3rd world for oil and resources is the reason your economies are starting to fail too. Most people in the US will pretend that their armies actions are pure humanitarianism
but we all know what decades of bombs and sanctions brings to the world...
time to reap what you sow...next time sow something nicer...