A central conflict in the history of mankind is that between Abrahamic monotheism and civilization. The words I chose are not accidental: the major Abrahamic religions (Judaism, Christianity, Islam) are closely interlinked and at their core all three are opposed to civilization and its source, reason.
It is noteworthy that Judaism and one of its fellow monotheistic religions, Zoroastrianism, emerged outside the main civilizational centers in the vicinity (Greece, Egypt, Babylonia) - among the Jews and Persians respectively. Both the Jews and Persians were at the time "barbarians" - i.e. they were relatively uncivilized tribes in the orbit of the Egyptian and Babylonian civilizations (I'm not implying that either the Jews or Persians are inherently barbarous - I'm just saying that they had not yet become sufficiently civilized by the mid-1st millennium BC but in later periods they might have become more advanced). Thus from the very start the onslaught of monotheistic religions was in essence the rise of barbarism in opposition to civilization. Traditional polytheism in Egypt, Babylonia and especially in Greece was less zealous and fanatical than Abrahamic monotheism and was gradually declining under attack from science and (in Greece) philosophy.
Judaism then spawned Christianity, the creed that destroyed the Greco-Roman culture. This phenomenon, which is either unknown to or ignored by most American conservatives, is one of tremendous importance. In a span of a few centuries, an enormously complex, sophisticated and advanced civilization was completely eliminated by Christian fanatics (the barbarian invasions were just a secondary factor made possible by civilizational decline).
The Greco-Roman culture was revived to a certain extent in Sassanid Persia and classical India and during the Arab-Persian Golden Age. These renaissances were ended by the third Abrahamic religion, Islam (along with Hindu irrationalism in India). Islam was not only heavily influenced by Judaism and Christianity but was a direct offshoot of the common Mosaic/Christian tradition. Indeed, Muhammad viewed himself as a successor to these prophets, in a similar vein to the Marx/Engels/Lenin apostolic succession. He scolded the Jews and Christians for not accepting him as the messiah they had themselves expected. Much of the Quran is based on Judaic scriptures and Christian apocrypha circulating in the Arabian Peninsula. Moreover, Christianity and Islam share many similar trends – such as attempts to purify religion, “go back to the roots” and eliminate the remnants of paganism (e.g. iconoclasm periodically recurring both in Christianity and Islam, as well as similarities between Wahhabism and Protestantism (especially Evangelicalism) on the other hand).
As you can see, up to the early Middle Ages Judaism, Christianity and Islam were basically parts of the same irrational tradition and fought on the same side - that of unreason, slavery and barbarism. Granted, the only major exception was the difference between Christ's "peaceful" message in the Gospel on the one hand and the cruel and bloody goings-on in the Old Testament and the Quran. However, this did not prevent Christians from approaching Muslims in the scope of atrocities and genocide. The reason is that any religion qua religion is based on faith. When faith, as opposed to reason, is accepted as the basic premise, people can't persuade each other through reasoning and are unable to deal with each other through non-violent means. Indeed, when reason is rejected, any concept - including freedom - becomes meaningless and undefinable. "Freedom is the freedom to say that two and two make four." Moreover, Jesus’ altruist tendencies also prove my point, since altruism has always been the favorite justification for massive-scale slaughter. “Progressive” humanitarians bestowing bread on the hungry and needy masses have always allied with the most brutal dictators.
It is only in later periods that an essential difference emerges between Islam on the one hand and Judaism and Christianity on the other hand. Both Christianity and Judaism integrated rational elements inherited from the Greeks and revived by the Scholastics and Humanists. Islam, though it did try to make concessions to reason during the Golden Age, ultimately rejected the rational Aristotelian heritage wholesale. In the 9th century, the Mu'tazilite school of kalam (Islamic theology), which attempted to reconcile faith with reason, was crushed by caliph Al-Mutawakkil (847-861). Since then, Islam has turned more and more irrational.
To sum up, two points should be made. Politically, Islam is now the main enemy, since it seeks to enslave mankind and slaughter those who refuse to be enslaved (unlike modern Judaism and Christianity, which do not aspire to such goals). However, intellectually, the inner core of Judaism, Christianity and Islam is still the same - it is faith, i.e. unreason. It is the cause of which the Islamic jihad is a result. The alliance between Judeo-Christianity and reason is temporary and fleeting, as any alliance between truth and falsehood. This alliance is already starting to collapse, with Evangelicalism becoming more and more mainstream. In all intellectual battles, it is the more consistent side that eventually wins. The Judeo-Christian tradition will be either won over by Abrahamic fundamentalism (thus allying itself with Islamofascism) or disintegrate and be replaced with a wholly secular philosophy founded on reason. One should always remember that, on the fundamental level, U.S. bible thumpers are on the same side with totalitarian Islam.
To win the war for our freedom, we must fight on two fronts – politically and militarily against Islamism and intellectually against Abrahamic irrationalism in general (including Judaism, Christianity and Islam). We must side with Aristotle against Abraham.