Gregory Warner

Tucked in the northeast corner of Africa, Eritrea is one of the most closed societies in the world, so much so that it's sometimes dubbed the "North Korea of Africa."

President Isaias Afwerki does not tolerate any independent media. The Internet is restricted. Reporters without Borders recently named it 179th out of 179 countries for freedom of expression.

For the past six years in Somalia, Western countries have been putting up the cash and African nations have been supplying the soldiers, a formula that has pushed back al-Qaida-linked militants and allowed Somalia to elect it's first democratic government in 20 years.

"We can fix our problems in Africa," says Brig. Michael Ondoga, a contingent commander with the African Union Mission in Somalia or AMISOM. "All we need is your support."

It's not at all hard to see why this plan is so agreeable to the American government.

As Kenya prepares for a presidential election next Monday, it's trying to prevent a recurrence of the last such poll, in December 2007, when more than 1,000 people were killed in postelection violence.

Last time, technology helped incite that violence. This time, the hope is that technology will help prevent a similar outburst.

Last time around, a text message came on Dec. 31, 2007, four days after a presidential election that many people in the Kalenjin tribe thought was rigged.

U.S. counterterrorism efforts include choking off the flow of cash to extremists, and urging friendly countries to help. But in Nairobi, Kenya, suspicion of Somali money — and an increase in terrorist attacks — has prompted a country-wide crackdown, with Kenyan police accused of extortion and arbitrary arrests of thousands of Somali refugees.

But how do you tell the difference between tainted money and honest cash?

Take Eastleigh, a neighborhood in the Kenyan capital, Nairobi.