Al-Qaeda is following the strategy of all times! Muslims ALWAYS tried to use others to make the biggest enemy their friend! Remember Mohammed himself: He tried to make Christians the enemies of Jews and the other way round. When he saw that this tactics failed, he used brutality and violence and committed mass murders against Jews and Christians of Mecca and Medina.
The same tatctics is used now by al-Qaeda: They see that the USA is an enormous but weakened power (since Obama is president) and they know that blaming Israel is just what many Americans want to hear, that "We didn't want to hit the US in first place, but we wanted them to open their eyes for the problems and struggle they are causing by supporting evil Israel". They think that thus many Americans say "hey, they are right, let's stop support for Israel and we will have peace". Ignoring the fact that the islamization of the US has already begun - in a subtile and creeping way: Muslim president, Muslim immigration, Muslim breeding, Muslim conversions (I have heard they are very successfully recruiting black Americans and people in jail).
Just watch comments on youtube and you will see the same tactics. One and the same muzzie wrote below one video "[censored] Germans once they killed the Jews and now they want to kill us!" Then they write "Jews are strange, they defend the f*cking Germans but it was the Muslims who saved them from the f*cking Christian Europeans" - and then the same person writes below anothe video "The Nazis haven't done their job properly, there are still too many Jews in the world"! They do either suffer from multiple personality (but this can't be the possible for so many people) or it is the tactics of provoking quarrels between friends in order to make them enemies! I think it is the second!