Editor's note: This is the fifth installment in a series of special reports that Dr. Friedman will write over the next few weeks as he travels to Turkey, Moldova, Romania, Ukraine and Poland. In this series, he will share his observations of the geopolitical imperatives in each country and conclude with reflections on his journey as a whole and options for the United States.

By George Friedman

We arrived in Istanbul during the festival of Eid al-Adha, which commemorates the willingness of Abraham to sacrifice his son Ishmael on God's command and praises the God who stayed his hand. It is a jarring holiday for me; I was taught that it was Isaac whom God saved. The distinction between Ishmael and Isaac is the difference between Hagar and Sarah, between Abraham and the Jews and Abraham and the Muslims. It ties Muslims, Jews and Christians together. It also tears them apart.

Muslims celebrate Eid with the sacrifice of animals (sheep and cattle). Istanbul is a modern commercial city, stunningly large. On this day, as we drove in from the airport, there were vacant lots with cattle lined up for those wishing to carry out the ritual. There were many cattle and people. The ritual sacrifice is widely practiced, even among the less religious. I was told that Turkey had to import cattle for the first time, bringing them in from Uruguay. Consider the juxtaposition of ancient ritual sacrifice so widely practiced that it requires global trade to sustain it.

The tension between and within nations and religions is too ancient for us to remember its beginnings. It is also something that never grows old. For Turkey, it is about a very old nation at what I think is the beginning of a new chapter. It is therefore inevitably about the struggles within Turkey and with Turkey's search for a way to find both its identity and its place in the world.

By Lukas Milevski

What is, and is not, unthinkable in defence and security depends upon the culture of the group doing the thinking. Culture is a web of narrative threads on issues, topics and themes relevant to a particular group. In terms of defence and security these narratives concern history, geography, the roles of force and law in society, and so on. Indeed, behaviour generally cannot be isolated from the culture of the acting group without making that behaviour random and meaningless. It is culture that gives meaning to thought and action. Culture is therefore in practice the sovereign context in which not just thinking and judgment take place, but also decision-making and doing. No analyst or decision-maker is autonomous of culture.

In practice, no state is a unitary political or strategic actor. A government is made up of a number of different ministries, occasionally conflicting, each with its own culture, and thus its own priorities, value judgments and methods of decision-making. At lower levels of granularity still, each ministry is itself comprised of discrete offices, each again with its own culture, occasionally conflicting with others, and so on. The holistic strategic culture of a state is therefore essentially an amalgam of a myriad of different tribal mentalities and cultures with the admixture of a sense of greater purpose not typically found within a single tribe itself. This does not just complicate decision-making, but also complicates the lesser task of consensus, due to the inevitable conflicts which will spring up in both discussion and action.

Within this context, friction is inevitable within a strategic culture among the various tribes of the defence and security community. Cracks appear in the façade and cannot be papered over, because disagreements are significant and the respective positions are too far apart to be reconciled among the various defence tribes. Such cracks represent issues dear to one or more of these tribes. These cracks thus represent 'unthinkables,' or issues for which certain outcomes are unthinkable for certain tribes.