Markets have become so accustomed to a surplus of oil in the global market that they are not as worried about tensions in the Persian Gulf region as they once were.

“Oil has become a broken barometer for gauging Middle East tensions,” said Helima Croft, head of global commodity strategy at RBC Capital Markets, an investment bank. “It now only reacts after something seismic happens.”

Ms. Croft said the markets had largely ignored the steps Iran had taken to respond to the reinstatement of American economic sanctions by the Trump administration. The United States and Saudi Arabia have said Iran was behind naval mines that damaged oil tankers and was behind an aerial attack on key facilities that temporarily cut Saudi oil production by more than half. These moves were apparently intended to demonstrate that Tehran would make it difficult or impossible for American allies like Saudi Arabia and the United Arab Emirates to export oil if the Trump administration hemmed in Iranian exports.

“I do not know how anyone can be sanguine about Iran’s disruptive capabilities after that drone/cruise missile attack,” Ms. Croft said. Saudi Aramco, the national oil company, managed to restore production remarkably quickly, but Ms. Croft said it was not clear that the company would be able to respond as fast to future attacks.

Analysts also say the drone strike on General Suleimani in Iraq may well worsen an already tumultuous political environment in that country. The killing has already sent ripples including calls from the Iraqi Parliament and government for the United States to withdraw its troops. Those in turn drew threats of sanctions from President Trump.

Iraq is the second-largest producer in the Organization of the Petroleum Exporting Countries after Saudi Arabia, and its oil fields have been largely unaffected. But there would be serious consequences if the turmoil spread to those fields, analysts say. For instance, the prolonged loss of half of Iraq’s exports, which amount to close to 4 percent of world supplies, could propel prices toward $90 a barrel, Mr. Tonhaugen said. And Iraq might not have the backup systems and other safeguards that allowed the Saudis to recover from the September attacks.

Mr. Tonhaugen and other experts are skeptical that Iran would resort to the “worst-case type of scenario” by trying to close the Strait of Hormuz, through which around 18 million barrels a day of oil is transported. Occupying much of the eastern side of the narrow strait, the Iranians can easily tamper with ship traffic there, but analysts are skeptical that they would do more than seize or target the occasional vessel, as they have in recent months.