There was a time when the mention of the Persian Gulf brought to mind images of pampered societies ruled by aging monarchs content to preside quietly over their oil money and fantastical skyscrapers while the U.S. kept the peace.

Not anymore.

A sudden royal shake-up in Saudi Arabia early Wednesday is only the latest wild card to be thrown in days of head-spinning developments in the typically staid Gulf.

The kingdom led nations in unexpectedly cutting off nominal ally Qatar from the clubby Gulf Cooperation Council, which suddenly looks so incredibly uncooperative that is has raised fears of war among its members. The fact that Qatar hosts one of the biggest and most important foreign U.S. air bases has so far proved to be a good insurance policy for the tiny emirate — but the dispute brings headaches for Washington.

The main adversary the Arab nations set up the council to stand against, Iran, meanwhile launched a volley of ballistic missiles at militants in Syria, its first such strike in more than a decade and a half.

That's not even getting into low global oil prices squeezing their largely petrodollar-driven economies. Nor does it account for the ongoing threat posed by the Islamic State group, which struck Tehran for the first time, or the stalemated war in Yemen that's led to extensive civilian suffering.

So what's actually going on? Some analysts have pointed to the fact that much of the turmoil came after U.S. President Donald Trump's trip last month to Saudi Arabia, his first state visit designed to show the Republican had a far different worldview than his Democratic predecessor Barack Obama. In truth, many of the tensions currently on display — with both Iran and Qatar — go back years. But Trump's strong public endorsement of Riyadh as his primary regional partner may have emboldened the Saudis and changed some of the geopolitical math.

Saudi Arabia and other Gulf nations like the United Arab Emirates were deeply suspicious of Obama's diplomatic detente with Iran, which culminated in the 2015 nuclear deal.

"The Obama administration's apparent attempt to disengage from the region engendered a change in the Gulf's strategic culture, making some U.S. partners more confident in their ability to act on their own," wrote Michael Eisenstadt, the director of the Military and Security Studies Program at The Washington Institute for Near East Policy.

However, "arms sales or military surges cannot compensate for policy errors and missteps whose effects are regional in scope and geopolitical in scale," he added.

U.S. Secretary of State Rex Tillerson's efforts at trying to mediate the Qatar crisis while Trump's own tweets appear to back the Saudi-led isolation over allegations the country supports terrorism have only compounded the uncertainty gripping the Gulf. Qatar long has denied backing extremist groups, though Western diplomats say its lax oversight allowed funding of Sunni militants like Syria's al-Qaida branch.

The State Department this week demanded the countries boycotting Qatar spell out their complaints, suggesting the Trump administration was losing patience over the spat among its Gulf partners.

In Iran, Tillerson's comments last week before Congress that the U.S. is working toward "support of those elements inside of Iran that would lead to a peaceful transition of that government" angered officials there already suspicious of Trump.

Meanwhile, citizens of Tehran openly accused Saudi Arabia of backing the Islamic State attack on parliament and the shrine of the Islamic Republic's founder that killed 18 people and wounded over 50.

Their evidence? Newly minted Saudi Crown Prince Mohammed bin Salman's own comments in May that the kingdom would "work so that it becomes a battle for them in Iran and not in Saudi Arabia."

So when Iran launched its first missile attack in over 15 years on foreign soil this week targeting Islamic State fighters in Syria over the Tehran assault, it openly acknowledged it was a message for Saudi Arabia and America.

That crisis between Iran and Saudi Arabia, which cut diplomatic ties in 2016, has extended into a disputed shooting in the Persian Gulf. Saudi Arabia said it captured three members of Iran's elite Revolutionary Guard aboard an explosives-laden boat that it alleges planned to attack a major offshore oilfield. Iran dismisses the allegation, though it earlier acknowledged the death of one citizen it called a fisherman who was shot by Saudi forces.

There's turmoil striking other Gulf countries as well, particularly the tiny island of Bahrain, which is linked to Saudi Arabia by a causeway. A government crackdown on dissent for over a year continues unabated. Militants have responded by stepping up attacks on security forces, including one Sunday that killed a police officer.

In Kuwait and Oman, citizens worry about the health of their current leaders, respectively the 88-year-old Sheikh Sabah Al Ahmad Al Sabah and 76-year-old Sultan Qaboos bin Said. In Oman, there's no clear successor to the sultan while in Kuwait, a leadership struggle is possible.

That challenge of continuing dynastic rule in Gulf Arab nations is tied to the task of handling burgeoning youth populations who expect to live as well or better than their parents. In Saudi Arabia, King Salman putting his assertive, 31-year-old son as next in line to the throne could prove popular with the kingdom's youth — if he can pull off his ambitious plans to wean the country from its oil-soaked economy.

That all could be derailed with the dissention among the Arab Gulf states in the region and the ever-heating war of words between Iran and Saudi Arabia. In a way, that trouble has been there for decades, simmering just under the surface.

Now it's boiling to a crisis at a level unseen since the 1990 Iraq invasion of Kuwait. That ended with a war and burning oil fields, something no one wants to see now.


EDITOR'S NOTE — Adam Schreck, the Gulf news director for The Associated Press, has reported from each of the Persian Gulf states and other locations across the Middle East since 2008. Jon Gambrell, an AP journalist since 2006, has covered the Middle East from Cairo and Dubai, United Arab Emirates, since 2013.


Follow Adam Schreck on Twitter at www.twitter.com/adamschreck . Follow Jon Gambrell at www.twitter.com/jongambrellap .