This gets at the very heart of why anyone bothers to study history. We study history to learn from the mistakes (and triumphs, though granted there are precious few of those) of the past. We use that study to help us to influence how we make decisions today.
Take, for instance, our lovely friend Mr. Bush. He figured invading Iraq would be a grand old idea - partially because he figured we'd be welcomed as liberators (I think Rumsfeld was the one who came out with that beauty of a line).
He (they?) failed to consider the long history of distrust between the West and the Middle East. He failed to consider the ramifications of calling the war in Iraq a "crusade" (one little slip, I know...still, that must have made a HUGE propaganda point for the other side). He failed to consider the lingering prejudice against English-speaking peoples in Iraq (the British weren't the nicest occupying authorities between the wars - Winston Churchill was actually the first person to suggest using gas against the Kurds to keep them in line). He failed to consider that the last time the West promised freedom from tyrants (the Ottoman Turks) to Iraq, it took thirty years of European occupation before they followed through on it. He failed to consider the widely publicized "military police actions" of the Cold War, so many of which seemed to crush popular sovereignty instead of grant it. Historically speaking, Iraq had no reason to trust us, and, in my opinion, that's the reason the Iraqi government isn't making any progress - they'd prefer to do it their way without us looking over their shoulders, because they don't trust our intentions.
How does this have anything to do with Mr. Ahmadinejad? While Mr. Bush failed to consider the historical ramifications of his actions, Mr. Ahmadinejad wishes to fabricate historical ramifications for his own political ends. What would you be saying now if George Bush had claimed that the people of the Middle East always welcomed our actions?