Sunday's protest was one of many scheduled around the world for "Global Day for Darfur" to mark five years of ethnic cleansing in Sudan.

CNN: 18 students arrested in Darfur protest at White House

For many around the world, including investors, Darfur blights the image of Sudan's capital like the mark of Cain.

NPR: Darfur Casts Shadow Over Khartoum's Ambitions

To some extent, the unusually generous response to the tsunami crisis may reflect a widespread, and largely justified, belief in rich countries that their money is more likely to be spent well on relieving natural disasters than on man-made humanitarian crises such as those in Congo and Darfur or, for that matter, on general development aid to the world's poorest countries.

ECONOMIST: Asia's tsunami

And, to date, the Islamists have been responsible for killing more of their fellow Muslims than any other population, not just in Darfur but around the world.

CENTERFORSECURITYPOLICY: Where are the liberal non-Muslims?