I suppose that if one were to delve into history, one could conclude that all nations are artificial. Someone put them together -- whether it was the Founding Fathers who formed the United States, or some mythic royals who assembled the Nordic states. But in the ongoing G2K discussion, we are presumably talking about contemporary times -- about nations that are "in play" right now because they fail the essential test of nationhood: the center does not hold.
Simply put, that means the national entity cannot be governed by an authority that's universally accepted within the geographical and political perimeters of the territory. Iraq and Lebanon aren't the only examples, sadly; just go up and down the list of the U.N.'s 192 member states and see how many are "failed states."
It was the fashion among development economists until not so long ago to aver that "failed states" were those that lagged economically and were unable to keep up with the progress registered by the general global cohort of nations. Their systems were corrupt. Their infrastructure was inadequate. Life expectancy was low. Literacy was feeble. Women were treated poorly. Foreign aid was misused. Domestic resources were mismanaged. A vast majority of such failed states were, obviously, in Sub-Saharan Africa; their traditional tribal cultures were often cited as impediments to modernity, and traditional blood feuds among tribes were often cited as major obstacles to good national governance. Africa, of course, is a prime example of "artificial nations" carved out arbitarily in the late 19th century by European colonial rulers.
But the concept of "failed states" seems to have changed in recent years. It now applies to territories -- such as Iraq and Lebanon -- where a concerted effort has been made by outside powers -- which is to say, Americans and their European allies -- to promote democracy and sustainable human development. That effort hasn't worked because neither "nation" has a "core" -- a center that can hold together what Jawaharlal Nehru once called fissiparous tendencies (he was referring to the Indian Subcontinent, of course). Scratch the surface in Lebanon, and Christian Maronites are for Christian Maronites; Sunni Muslims are for Sunni Muslims; and Shias are for Shias. For many years they stayed together in a dubious arrangement of convenience -- but there never was a strong center that could accelerate economic development and truly strengthen the idea of a polity that could accommodate, absorb and assimilate.
And Iraq? Well, look up the news headlines any hour and judge for yourself whether there's a center, and whether it can hold.