When Americans think about the Nazi era or Imperial Japan, they compare it with contemporary US, the last 40 to 50 Years. Most young Americans are not able to include in their thinking that:
1.  The 20th century started in the 19th. What I mean is: the World was still a large World with many unexplored places and less homogeneous than at this time.
2. and other parts of the world have not had the same pace of development.
3.  and did not start out at the same level as the US.
4.  and that global transportation as we know now started not that long ago.
5. and it is less than forty years ago that Martin Luther King Walked.

There are some countries in the world who have "cultures" if I may call it, who are thousands of years old and in some aspect at least 1000 years behind in development. Among those are many countries in Africa as well in West, Middle and East Asia and lets not exclude China, Mongolia and Tibet. Tibet is a peace loving culture; they are not a problem.
Afghanistan, the country where the alleged instigator of the terror attacks, Usama bin Laden, seems to reside, is a extreme case. Communists took power in that country. However groups of religious Moslems naturally rebelled against that regime, because communism is anti any form of religion. That's the nature of the beast. That is why the US gave support to the rebels.
After several years of bloody fighting with the Soviet Military, who had been send to assist the local communist government, and while supplied with weapons, stinger rockets, by the US, these nationalists groups caused so much losses to the Soviet troops, that it was called Soviet Union's Vietnam. 
Eventually the Soviets withdrew; the homeland could not afford the war anymore. A  power struggle ensued between the separate nationalist factions and warlords who could claim victory over the Soviets. This struggle is still going on. However a coalition of several of the rebel groups formed the Taliban. This, the de facto government of the larger part of Afghanistan, instituted a regressive Medieval Islamic society. The world view this society has is to continue the conquest of the World by Islam, started some 1340 year ago, to establish a theocratic society.

Shortly ago I saw a "Discovery Channel" so called documentary about the transition from Neanderthal to Cro-Magnon humanoid periods.( Note the critical tone "so called". About that later.) That transition has taken place in some fashion. But we really don't know how; scientist speculate and have theories how this took place.
The fact is that Neanderthal declined and disappeared wile Cro Magnum took over the evolutionary baton. 

The USA has a struggle on its hands as the modern society with the medieval faction of Islamic society. The outcome will inevitably be our continued existence. But the Civilized World better realize that they have a bloody job on their hands. They might need to do a lot of killing, to rid this world of Pre Modern Society Humanoids. 
Doesn't that sound like racial cleansing? Will we be able to spare the innocent? Women and children? Girls and Boys? What will become from those boys, who's fathers have been killed or imprisoned? Will they not hate the group which caused their loss? Look to the Palestinians who never lived in Palestine because they are born after the proclamation of the State of Israel. 

Where is their hate coming from? We know, we helped establish a nation called Israel. This is a fact we can't go back on. Why did it happen? Out of guilt. 1930 years ago Jews of that time where, again, scattered, it happened before. This time they scattered around the Mediterranean, out of Palestina. After all that time, 1900 years, some Jews went to, worked in and bought land in Palestina . One by one they came; piece by piece they bought and took over the land. Then after the WWII, they had so much sympathy, desperation and power that the UN accepted their settlement and proclamation of independence. 
Why did the western world take the side of the Jews? Because of Jesus, who was a Jew and, sorry, Christian indoctrination. I remember, I was 12years, when I heared over the radio that Israel had proclamed their independece and it made me happy; I was going to a Christian school. An other reason is guilt; like "the Nanny" said: "guilt has been very good to our people".

Let me make some imperfect comparisons: 
There are some people who moved in a mostly empty apartment building. After the superintendent discovers that they where there, they pay him some money. The pay not rent; actually they contribute to the maintenance and upkeep; they also do a good job fixing up the building where they now live. However, they are squatters. After a while the owner wants his close family to move in. But the squatters say we paid, fixed up, we infested in this building, we won't leave. The owner is not happy and he and his whole family holds a grudge. Well, now we should  some what understand the Palestinians. 
What has Usama bin Laden to do with it? He is the far far family of the owner family. He is a street smart (desert smart) bully. And he had some dealings with, and does not like the people who support the squatters.
Any time he gets the chance, he beats up squatter or supporter regardless of whether they are women or children: he is a tough Neanderthaler. 

If you did not get it: The US are the people who support the squatters.
I told you: it's an imperfect comparisons. It is more complex.

The Moslem World has the ideal of Allah's World order implemented NOW, under one faith; however they have an incomplete concept of what Allah's Ideal is.

The Western World has the idea of an evolution or incremental improvement of society, starting out with freedom. Freedom to believe or not. Freedom to live their life as long as they keep within secular laws. It includes all faiths. 

This is the simplified principle. It is here not the place to completely explain all differences an approaches and views according both World views. These views are fundamentally differed. 

Both World view's proponents consider theirs superior. Neither is! There are in both Views some good aspects amiss.

The attack on the United States of America, is an attack on Western society, culture, world view and derives from thinking, regressing to Mohammed's time of conquering the Ismaelite World ( decedents of Ismael, son of Abraham and Hagar).

When the US not understand that there will be no end to the war against the "terrorists among the Moslems", unless and because the World view has to be eliminated. This will bring the US and allies against all Moslem Theocracies. This will mean Armageddon!

Good Luck, Mr. President, We hope you are the right person to lead this fight; You are part of God's Providence! You know that. That God may advice you though the Messiah!