1. What’s caused the diplomatic rift?

          It’s mostly, but not all, about Iran. The spark for this flare-up was a report by the state-run Qatar News Agency that carried comments by Qatar ruler Sheikh Tamim bin Hamad Al Thani criticizing mounting anti-Iran sentiment. Qatari officials quickly deleted the comments, blamed them on hackers and appealed for calm. Criticism by Saudi and U.A.E. media outlets escalated after Sheikh Tamim phoned Iranian President Hassan Rouhani over the weekend in apparent defiance of Saudi criticism.

2. So this is a Sunni vs Shiite tension?

          Partly. The Shiite-led Islamic Republic of Iran is Sunni-led Saudi Arabia’s main regional rival. The two major oil exporters are on opposite sides of conflicts from Syria to Iraq. In taking diplomatic action, the Saudis cited Qatar’s support of “terrorist groups aiming to destabilize the region,” including the Muslim Brotherhood, Islamic State and al-Qaeda. They accused Qatar of supporting “Iranian-backed terrorist groups” operating in the kingdom’s eastern province as well as Bahrain.

3. Why is the spat taking place now?

          The temperature noticeably rose following Trump’s visit. Days after Trump and Saudi King Salman bin Abdulaziz singled out Iran as the world’s main sponsor of terrorism, Saudi Arabia and the U.A.E. accused Qatar of trying to undermine efforts to isolate the Islamic Republic. Newspapers, clerics and even celebrities attacked Qatar’s Sheikh Tamim; the Riyadh-based Al-Jazirah daily accused him of stabbing his neighbors with Iran’s dagger.

4. What do analysts say?

          Emboldened by closer U.S. ties under Trump, the Saudis and the U.A.E. are seeking to crush any opposition that could weaken a united front against Iranian influence in the Middle East. The two countries are also putting pressure on Qatar to end its support for Islamist movements such as the Muslim Brotherhood and the Palestinian Hamas group that rules the Gaza Strip.

5. What does Iran say?

          Iranian President Hassan Rouhani, a moderate cleric who was re-elected to a second, four-year term last month, says his country is ready for talks to resolve the crisis. At the same time, though, Iran’s Supreme Leader Ayatollah Ali Khamenei, who wields more power than Rouhani, has said the Saudi regime faces certain demise for its policies in Yemen. In 2015, Saudi Arabia assembled a coalition of Sunni-led countries to fight Yemeni Shiite rebels loyal to Iran after they toppled a Gulf-backed government. The war there continues.

6. Where else are Saudi and Iran facing off?

          They are locked in proxy wars on opposite sides of conflicts across the region from Syria to Yemen. Suspicions that cyberattacks on government agencies in Saudi Arabia emanated from Iran threatened to elevate tensions between the two powers in late 2016. Earlier that year, after Saudi Arabia executed a prominent Shiite cleric, Iranian protesters set the Saudi embassy in Tehran on fire, and Saudi Arabia severed diplomatic relations with Iran.

7. Are disagreements with Qatar anything new?

          In 2014, Saudi Arabia, the U.A.E. and Bahrain temporarily withdrew their ambassadors from Qatar. That dispute centered on Egypt, where Qatar had supported a Muslim Brotherhood government while the Saudis and U.A.E. bankrolled its army-led overthrow. Qatar also hosts Hamas’s exiled leadership as well as Taliban officials. Analysts say Saudi and its allies want to show Qatar, a country of 2.6 million residents, that.

8. Isn’t that what Qatar tries to do?

          Less so now than in the Á. During the Arab Spring uprisings Qatar, uniquely among Middle Eastern governments, broadly supported groups agitating for change — as long as it was outside the Persian Gulf. Muslim Brotherhood groups have mostly \Æsince, and Qatar reeled back its support for them in 2014 when faced with diplomatic threats from its Gulf neighbors. Qatar also aspires to be the region’s indispensable mediator. Its leaders have connections with a wide range of parties, such as warring tribes in Libya as well as both the U.S. and the Taliban. On the other hand, by choosing sides during the Arab Spring revolts, it weakened its standing as a neutral party.

9. What else is Qatar known for?

          It’s the world’s biggest exporter of liquefied natural gas, has the world’s highest per-capita income ($129,700 a year), will hold the 2022 FIFA World Cup and hosts the Al Jazeera television channel. When Saudi Arabia ejected the U.S. air operations center for the region in 2003, Qatar took it on. Today the emirate hosts 10,000 U.S. troops. (Trump last month held talks with Sheikh Tamim to discuss Qatar’s purchase of American military equipment, and said the two countries have “been friends now for a long time.”)

10. What are the repercussions for markets?

          Any dispute in the region will make oil markets nervous. Internal disputes among the Gulf countries could limit their appeal to foreign investors. Even before Trump’s visit, Citigroup said rising tensions between the U.S. and Iran could also have “significant”’ implications for oil and financial markets. Qatar stocks plunged more than 5 percent at the open on Monday.

11. Why might this dispute be different?

          “Internal differences and disagreements are nothing new, but what is interesting is the timing and the somewhat unprecedented level of pressure,” says Mehran Kamrava, director of the center for international and regional studies at Georgetown University in Qatar, referring to the recent Trump visit. That suggests that “Saudi Arabia and the U.A.E. want nothing but complete submission from Qatar.’’