Islamic terrorists planted 12 backpack bombs and the Spanish people surrendered. They immediately switched from supporting a Spanish government that had backed the war on terror to electing a socialist enemy of the war on terror. We now have a scientific measure of Spanish instincts. They can be described in one word: female.

Faced with the choice of whether to fight against a violent invasion or surrender to it, men and women face very different, sometimes opposite, biological imperatives. Throughout mankind’s evolutionary history, if a man fought against an invader he risked death in proportion to the strength of his foe, while if he surrendered, he faced almost certain death, at least in the biological sense. At best he would be enslaved and denied further access to females. Thus the reproductively more successful strategy for a man would almost always be to fight invaders, and this is how we should expect the male instincts to be programmed, according to the precepts of evolutionary psychology.

For a woman, fighting against an invader also risks death, but surrender offers much better reproductive prospects for women than for men. A woman’s reproductive capacity is part of the booty, often the primary booty, that invaders have always been after. Thus a fertile woman could almost be guaranteed that, with surrender, her reproductive capacity would not be wasted. This difference in biological incentives will have left women with stronger instincts to surrender.

The disparity between male and female instincts is watered down by the biological incentives that men and women have in common. Both have incentive to save their existing children from being killed or enslaved, especially their boys. (Enslaved girls will still reproduce.) But the disparity still remains. Women with children should have a marginally stronger instinct to surrender than men do, while young childless women should have a much stronger instinct to surrender.

The poll watching group Public Opinion Watch has commented on what it calls the “interesting paradox” that “women are substantially more worried about being victims of a terrorist attack than men, yet appear to be substantially less supportive of the Bush administration’s Iraq policy, ostensibly designed to protect American citizens from terror.” This “paradox” can be taken as a measure of the greater female instinct to assume a submissive posture.

Demographers have also found that America’s appeasement party—still officially called the Democrat party—is the party of single women, while the Republicans are the party of married women. In this case, however, the statistical gap probably overstates the female lay down effect, due to entanglement with other factors. Many single mothers effectively marry the government by going on welfare, and since the Democrats created welfare, they see the Democrats as the husband figure in this relationship. Some of these women might well want to fight to protect their children, but still go with the party of appeasement because they are married in.

Anthropological evidence is available from the discovery of the primitive Yanomamo people, hidden deep in the rain forests of South America. When Napoleon Chagnon studied the Yanomamo (“the fierce people”), he discovered a violent society where a quarter of the men were killed by other Yanomamo, mostly in woman-stealing raids between different Yanomamo tribes. Having to survive as a prize of war was very common for Yanomamo women. Add territorial conquest to the equation, where fighting invaders becomes even more of an imperative for men, and the difference between male and female instinct becomes even stronger.

There is no suggestion here that male instinct is inherently better than female instinct. It is, however, manifestly better as the rational strategy for a nation. To appease aggressors is always and everywhere to encourage them. Osama Bin Laden has listed the return of Andalusia to Muslim domination as one of his primary objectives. To Al Qaeda, no Muslim state must ever become non-Muslim, and Spain is the most prominent example of Muslim reversal. Terrorist ambition is fixed squarely on Spain as its first western conquest.

For a modern nation to surrender to a band of primitives over twelve backpack bombs is insane. You can always submit later, senoritas, after Spain has been defeated. There is no immediate need to get down on your backs. That is just your sex talking: the terrified Yanomamo girls inside, hoping to survive. The personal must not be political, not the female personal, not when the nation is under attack.

Unfortunately, everything is personal for women, including politics, at least at the level of biological disposition. Women, throughout our evolutionary history, have lived their lives under the power of men. While men have looked outward, engaging the world outside the home in order to provide for the home, women have looked inward, managing the household and establishing their status in it through their emotional relationship with the resident political authority, the man. Men and women both have the same open ended faculties to discover and pursue value, but the difference in our instinctive natures is large.

Faced with an invader, the combination of woman’s instinct to submit, and the tendency for her political thinking to revolve around the personal, can be a disastrous pairing for a nation that allows women to vote. The problem is even worse in Europe because European society has become thoroughly feminized. The European man no longer thinks like a man.

How is it possible for male instinct to be occluded? Very simple: instinct is shaped by calculations of reproductive benefit, crunched numerically by natural selection. Our open ended faculties of intelligence grasp and reinforce these calculations. By changing the conditions in which boys are raised, the risk-reward calculations they face can be shaped so as to set their rational faculties against their instincts, causing instinct to be suppressed.

Consider the impact of European civilian disarmament. Every Spanish man, from the time he was a boy, has been deprived of the means to defend himself and others. Faced with any serious violent threat, from as little as a knife or a piece of pipe, he has always been at a total disadvantage. His open ended faculties of intelligence have always understood clearly that his only rational course is to flee.

The normal male biological calculation— that it makes sense to fight in defense of self and others—is conditioned (in our evolutionary number crunching) on a man having done what he can to be prepared to fight. Our ancestors did not disarm themselves! Europe, by not allowing its boys ever to be prepared to fight, sets their rational faculties to overcome their biological nature. Instead of coming to grips with the moral use of force, European male character formation all occurs in conditions that push males to the female calculation: that it is better to submit.

The result is a vagina monologue. European males and females both see the world in the instinctive female way, as the Spanish displayed last month. By choosing not to fight for their survival, the Spanish are, at the biological level, seeking to survive by making babies for the invader. Here in America, our women (or at least our Republican women), grow up thinking of themselves and their men as armed. Thus their rational faculties grasp that it makes sense to fight. Faced with an attacker, it is the female instinct that gets overruled.

Such good girls, even helping out behind the lines while our boys methodically stuff the Jihadis into the meat grinder. There is a long way to go, but women, don’t worry. We will never let the vermin take you. You can go to them if you want, the flakes amongst you. We allow you your weakness. What we love is your strength.

Alec Rawls is a contributing editor of The Stanford Review. He is currently writing a book on republicanism. Contact alec@rawls.org or visit www.rawls.org.