2) Get Our Military Out of the Middle East. If we pull out of the region entirely, terrorism will not be eliminated, but it will be greatly reduced. Why? Because the main complaint of Muslim extremists--and non-extremists--is Western influence and interference in their part of the world. Osama bin Laden's stated reason for 9/11 was American involvement in Saudi Arabia and elsewhere in the Arab world. "They hate us for our freedom" is no more than a Republican talking point. Let the Sunnis and the Shiites kill each other if that's what they want to do, but we don't need to be involved in that.
3) Limited Military Action. Just to clarify, I'm not advocating appeasement. If there is reliable intelligence about planned attacks on Western targets, surgical military strikes by coalition governments would be appropriate. But lets make sure no U.S. or Western ground troops are involved. That would only make the situation worse.4) The Most Radical Idea of All: Assisting the Muslim World. Think of the money we would save if we withdrew our military from the Middle East. Then imagine what would happen if we used some of that money to help our former adversaries. Imagine what the average Muslim would think if Western nations, instead of invading their countries militarily, came to their lands, with their permission, to help them---building schools, providing health care, and building (or rebuilding) roads, bridges, and other infrastructure. Americans and other Western countries could send thousands of non-combat soldiers and citizens invested in making the Muslim world more modern, secure and friendly.
I don't expect these acts of assistance will immediately stop all terrorism and hatred of the West. What I'm proposing is a long-term strategy, not a short-term one (the kind we are fondest of). Muslims will naturally be suspicious at first, but once real assistance was in place, they might start to look at Western powers in a different way: as (gasp!) friends. Terrorism would eventually dissipate. There would no longer be a compelling reason to seek revenge on the West. No guarantees here, but one thing we can count on: staying the course or doubling down militarily will not work.