The upheaval that put President Hosni Mubarak on a collision course with popular will is still being felt across the Middle East, reaching autocratic regimes from Yemen to Iran.
In a region coveted for its strategic and natural resources, a mix of Islamist and pro-democracy voices have demanded the ouster of the old, oppressive guard in favor of new political horizons. Following the example set by Egypt, thousands of protestors filed into their city's respective streets, each forgoing the relative safety of the status quo for an uncertain shot at self-determination.
The future is still unwritten for the democratic reformers in Algeria, Bahrain, Iran, and Yemen. As of today, unpopular governments remain at the helm, dispatching riot police to quell civic unrest before their capitals erupt into the next Cairo.
What's clear is that the present order is untenable, and change, in one form or another, is coming to the Middle East. Below are four hot spots, and a quick study of what's causing the heat.
Algeria: After 19 years suffering under "emergency law," which provided President Abdelaziz Bouteflika with enhanced authority and stifled the public's right to protest, a mass of Algerian opposition won a key victory Monday with official word of the unpopular provision's repeal.
But the emergency law's recall does little to resolve the country's stagnant economy, which remains high on the list of Algerian concerns.
This week, 10,000 protesters marched on Algeria's capital to demand Bouteflika's early retirement. Outnumbered three-to-one, the pro-democracy protesters clashed with 30,000 riot police, who took at least 400 people into custody, including several foreign journalists.
Like Tunisia and Egypt, high unemployment, poor housing, and an overwhelming gap between rich and poor fuel the protests in Algeria. Unlike Egypt, Algeria's ruling elite can hedge its oil wealth against popular grievances to buy a little more time in power.
Bahrain: Police fire left one man dead at a funeral for a protester killed in a separate anti-government demonstration, setting off a storm of fury in Bahrain that led to the defection of the main opposition party from parliament.
While the force of Egypt's uprising ended President Hosni Mubarak's 30-year reign in just 18 days, protesters in the kingdom face some heavy lifting should they seek to eject King Hamad bin Isa from his throne; the monarch's Al Khalifah family has been at the helm of the Persian Gulf nation for more than two centuries.
Unlike Egypt's rebellion, the landscape of Bahrain's push for reform is rife with sectarian tension. The royal family, like most of the ruling elite, follows the Sunni sect of Islam and maintains close ties to the Arabian peninsula. Bahrain's majority, meanwhile, is Shiite, and looks toward Iran for its cultural and political cues.
Historically excluded from government posts by political apartheid, Shiites protesting in Bahrain's streets are beating a drum for equality, not just democratic reform.
Iran: Thousands defied a ban on demonstrations and took to the Iranian streets in the past few days, calling for the ouster of President Mahmoud Ahmadinejad. Peaceful demonstrations are permitted under Iran's constitution, but the powers that be disregarded established law and set Iran's security forces on protesters, leaving dozens injured and one dead.
In a speech marking the 32nd anniversary of Iran's Islamic Revolution, Ahmadinejad praised the revolutionary turn in Egypt, assuring “the Iranian nation is witnessing the echo of its voice in other parts of the Muslim world.” Days later, Ahmadinejad's government called for the execution of opposition voices.
Iran's official incongruity wasn't lost on Obama.
"I find it ironic that you've got the Iranian regime pretending to celebrate what happened in Egypt, when in fact they have acted in direct contrast to what happened in Egypt by gunning down and beating people who were trying to express themselves peacefully," the president said at a White House news conference.
Yemen: After five straight days of protest in the capital San'a, pressure is threatening the rule of President Ali Abdullah Saleh, who has occupied the seat of Yemeni power for almost 32 years.
What began as a series of small demonstration in support of Egypt's popular revolt grew into a sustained and cohesive call for revolution in Yemen. Strategic tribal alliances that extend into Yemen's parliament have so far kept Saleh in the presidential palace, but in the wake of the regime's forceful crackdown on protesters, long-held allegiances are being second-guessed.
Saleh and his opposition both warn that bands of heavily-armed tribes could seize power and crush any hope of law and order should the government collapse. The beleaguered nation's political parties have never held much jurisdiction over the tribal lands spreading far and wide outside its capital.
An earlier round of protests forced Saleh to make political concessions to his protesters, including a promise to quit politics after his term expires in 2013.
Evidently, that wasn't enough.