Washington (CNN) -- Bahrain -- a tiny group of islands where hot political rhetoric meets cold military reality.
As far as Washington is concerned, this small Persian Gulf kingdom may be where support for Middle East democracy dies. The loss of American military power that could accompany an overthrow of the regime of King Hamad bin Isa Al Khalifa is incalculable.
Nestled between Saudi Arabia and Qatar, Bahrain is home to 1.2 million people. More importantly, it's home to the U.S. Navy's Fifth Fleet -- a vital instrument for the Pentagon in both Afghanistan and Iraq. Fighter jets from carriers in the fleet provide close air support for American troops in Afghanistan.
The fleet is also a potential bulwark against a future nuclear Iran, analysts note.
"It's our most important strategic asset in the Persian Gulf," said Michael Rubin, a former Bahrain resident and Middle East expert at the American Enterprise Institute.
The security of America's naval presence in Bahrain was called into question when protests erupted there this week. Three people died and dozens were injured Thursday when security forces stormed a group of protesters. Witnesses described a blunt show of force, with police firing pellets and rubber bullets, as well as using tear gas.
Two other people died during disturbances earlier in the week.
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Secretary of State Hillary Clinton said in response that the United States has "deep concerns" about the crackdown. Future protests should "not be marred by violence," she declared.
"Violence is not an appropriate reaction," lectured White House Press Secretary Jay Carney. Leaders in Bahrain and across the Middle East region need to "be more responsive" and "live up to the hopes and dreams of their people."
But exactly how responsive?
Bahrain has been ruled by a Sunni Muslim royal family since the British left in 1971. Two-thirds of its population are Shiites. While the latest turmoil is largely a reaction to uprisings in Egypt, Tunisia, and elsewhere, younger Shiites have routinely led protests -- often violent -- to complain about discrimination, unemployment and corruption.
They also rioted when the Islamic Revolution toppled the Shah of Iran in 1979. Since then, every time Shiite protests have become too heated, the Sunni rulers of Saudi Arabia have quietly sent troops into the country, according to Rubin.
"On the one hand, Bahrain is a flash point between the United States and Iran," he told CNN. On the other, it's "a flash point between Saudi Arabia and Iran."
Bahrain was actually a Persian province through the 16th century. Iran claimed the territory when the Britain left, but the Bahrainis opted for independence.
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"Bahrain is Iran's Kuwait," Rubin said, referencing former Iraqi strongman Saddam Hussein's insistence that Kuwait was rightfully an Iraqi province.
If Bahrain's government falls, "there is no question -- no ifs, ands or buts -- Bahrain would become an Iranian satellite, and the Fifth Fleet would be sent packing," Rubin predicted.
The Obama administration is "not being too vocal on the riots in Bahrain because it's pretty much the one country where we can't afford regime change," he said.
Could U.S. officials find a new naval home in the Gulf? Possibly Qatar or the United Arab Emirates, Rubin said, but "if there's a sense that the dominoes are falling and the United States is the big loser, then all the regional states are going to make their accommodation with Iran whether they like us or not."
The stakes could not be higher.
