In the last four weeks, Elon Musk has offered a peace plan for Russia and Ukraine that outraged Ukrainian officials. He has posted a tweet about Iranian internet access that exposed government protesters to a phishing scheme. He has also suggested in a newspaper interview that China could be appeased if it were given partial control of Taiwan. An official in Taipei demanded that he retract his suggestion.

Mr. Musk has in recent months emerged as a new, chaotic actor on the stage of global politics. While plenty of billionaire executives like to tweet their two cents on world affairs, none can come close to Mr. Musk’s influence and ability to cause trouble. He has sometimes waded into situations even after he was advised not to, and has already left behind plenty of messes.

While the bulk of Mr. Musk’s wealth comes from his stake in his electric car company, Tesla, his influence stems largely from his rocket company, Space X, which runs the Starlink satellite network. Starlink can beam internet service to conflict zones and geopolitical hot spots, and it has become an essential tool of the Ukrainian army.

Mr. Musk’s influence will grow even further if his planned purchase of Twitter is finalized on Friday as he has promised. He has called himself a free speech absolutist, and he is expected to take a light touch to moderating Twitter’s content.

His critics — and there are many — worry that it is difficult to separate Mr. Musk’s opinions from his business interests, especially when it comes to Tesla, which is increasingly dependent on China.

“Technology has become central to geopolitics,” said Karen Kornbluh, a director with the German Marshall Fund, a geopolitical think tank, and a former adviser to President Barack Obama. “It is fascinating and it is messy and there is Elon Musk in the middle of it.”

In some cases, Mr. Musk has been a boon. When he provided Starlink internet access in Ukraine earlier in the year and funded at least part of the hardware and service, he equipped both civilians and soldiers with a crucial means of communication during the ongoing conflict with Russia.

But the messages he has delivered have also caused problems. Last week, in a Twitter post, he said he could not “indefinitely” fund Ukraine’s use of Starlink, before suddenly reversing course.

Late last month, Mr. Musk attended a private event in Aspen called The Weekend. Organized partly by the former Google chief executive and government adviser Eric Schmidt, the event brought together American business and political leaders, including Speaker of the House Nancy Pelosi, former Vice President Al Gore and the former chairman of the Joint Chiefs of Staff Joseph Dunford.

At lunchtime, under a tent on a golf course, Mr. Musk took the stage for a sweeping conversation with the billionaire businessman David Rubenstein, according to two people who attended the event and spoke on the condition of anonymity.

At the end of the conversation, to the surprise of many in attendance, Mr. Musk proposed a peace plan for the war in Ukraine that would allow Russia to annex Ukrainian land, seeming to align himself with the Kremlin.

The idea outraged many at the event, according to attendees. The next day, Jake Sullivan, the national security adviser to President Biden, gave a video talk at the event and a questioner raised the issue of Mr. Musk’s peace plan. Mr. Sullivan did not comment on Mr. Musk’s remarks at the event, according to a National Security Council spokesperson. Nonetheless, Mr. Musk revealed his plan 10 days later on Twitter. The Kremlin publicly supported the idea.

President Volodymyr Zelensky of Ukraine and his top aides fiercely rebuked Mr. Musk’s plan. But his shifting positions put them in a bind: Starlink terminals have become a crucial means of communication for the Ukrainian Army.

Mr. Musk did not respond to several requests for comment.

In mid-September, as the army advanced into southern territories previously occupied by Russia, it lost access to Starlink in some areas near the front lines, four people with knowledge of the matter said. Two of them said this was because Mr. Musk had “geofenced” the service so that it was available only in certain areas. It was not clear why the satellite system was not working, and others in Ukraine reported that it was working fine.

Mr. Musk has discussed the matter with both the Ukrainian government and the U.S. government in an effort to determine the locations where the army will have access to Starlink, according to the people. A National Security Council spokesperson said that the council, the Treasury Department’s Office of Foreign Assets Control and “officials across the U.S. government have spoken to Starlink and answered questions about U.S. policy like we do with all companies.”

This month, Mr. Musk delivered more uncertainty to Ukraine when he said he could not keep paying for Starlink service to the country, making it seem like he was shouldering the expense. In fact, the United States, Britain and Poland have paid SpaceX for at least part of the Starlink cost, according to a document outlining the expenditures reviewed by The New York Times.

“He has to decide whether Starlink is a commercial service that provides sometimes lifesaving technology to its customers or a service that is highly dependent on the geopolitical interests of its management and, thus, unreliable for customers who have concerns over national security,” said Dimitri Alperovitch, co-founder of the Silverado Policy Accelerator, a geopolitical think tank in Washington.

While he was in Aspen laying out his peace plan for the war in Ukraine, Mr. Musk also waded into unrest in Iran.

As protests spread across the country and the authorities responded by blocking internet access in some areas, he appeared to come to the rescue. “Activating Starlink,” he said in a Twitter message after the U.S. government lifted some sanctions that limited the ability of American tech companies to operate in Iran so that they could aid protesters.

Starlink offered the potential to bypass the government’s blockade of land-based internet connections that had taken Iranians in many cities offline.

But as ma