You hardly ever hear them blame the actual rulers of Gaza.
Here is a music video from Hamas' Al Qassam Brigades showing them manufacturing weapons - from existing water pipes that they dig up from the ground.
In the conflict's final days, Islamic Jihad leader Ziad Al-Nakhala boasted about his group's ability to improvise weapons from everyday materials.
"The silent world should know that our weapons, by which we face the most advanced arsenal produced by American industry, are water pipes that engineers of the resistance turned into the rockets that you see," he said.
And the world will continue to blame Israel for Hamas redirecting humanitarian aid to weapons and tunnels.