Lately, financial markets appear confused.

Oil prices recently hit their highest level since the start of the war in Iran, stoking broad worries about inflation and a global energy crisis.

Yet, it has been the best month for the stock market of President Trump’s second term. The S&P 500 ended April nearly 10 percent higher than where it ended March.

The last time the index rose more than 10 percent in a month was in November 2020, after Joseph R. Biden Jr. was elected president and early trials for Covid-19 vaccines showed promising results. On Friday, the S&P 500 rose a further 0.5 percent, putting it on course for a fifth straight week of gains.

To many outside observers, it seems incongruous that the oil market can be sending such a dour signal, while stocks reflect a strong sense of investor optimism.

But in this unusual moment, according to analysts and traders, bullish and bearish market signals can both be true.

While the stock market reacts to day-to-day news, it is primarily concerned with how that news affects the longer-term outlook for company earnings. Stocks initially fell when the United States and Israel attacked Iran on Feb. 28, reflecting uncertainty about the war’s duration, its impact on energy supplies and the fallout for corporate America.

Stocks began to rise again after the Trump administration and Iran started to de-escalate at the end of March, moving toward a cease-fire on April 8. The standoff between the countries has not ended, a peace agreement has not been reached, but for stock investors, the expectation is that the disruption to oil markets and supply chains won’t last much longer.

And the economic impact of the war, at least as far as the United States is concerned, has been manageable. Data on Thursday showed that the U.S. economy grew at an annual pace of 2 percent in the first three months of this year, boosted by spending on infrastructure by many of the big tech companies that have led the S&P 500 stock index to repeated new highs.

This week, Alphabet, Amazon, Microsoft and Meta, which collectively account for 20 percent of the S&P 500’s market value, said they had spent a combined $130 billion on data centers. The share prices of these members of the so-called Magnificent 7, a group of companies that also include Apple, Nvidia and Tesla, rose nearly 15 percent in April.

Strong earnings in other industries have also buoyed the market. Roughly a third of the companies in the S&P 500 have reported their financial results for the first quarter, and their average growth in earnings stands at roughly 15 percent, on course for a sixth straight double-digit quarterly rise.

Oil prices are a much shorter-term measure of investor sentiment than stock indexes. The oil market is primarily traded using futures contracts, which are derivatives that fix the price today for delivery at a specified date in the future. The most frequently cited oil prices refer to the next month or two. That means that changes in the conflict that could extend or shorten its duration by a few weeks show up in the price of oil but not necessarily in the stock market. Oil traders are fixated on the price of a barrel of crude in July, for example, while pension fund managers are thinking about market returns many years in the future.

This week, a deadlock over the future of Iran’s nuclear program appeared to threaten the fragile cease-fire with the United States, helping to push the price of Brent crude, the international oil benchmark, to a four-year high, of over $120 per barrel on Thursday.

But investors appear to anticipate some sort of resolution the further out they look. Futures contracts for deliveries of Brent crude in December still trade below $90 a barrel.

“While the geopolitical environment remains fluid on a day-to-day basis, markets appear to be assigning a higher probability to a relatively near-term U.S. exit from the Middle East, alongside a normalization in global supply chains that could ultimately pressure oil prices lower,” said Adam Turnquist, chief technical strategist at LPL Financial.

The timing of the Trump administration’s announcements of important changes in policy in the conflict with Iran have, to some extent, exacerbated the appearance of market moves — both on the way down and the way back up.

The war began after the market closed on the final day of February and the cease-fire was announced on the final day of March, so the stock market’s losses were concentrated in March and the recovery almost entirely captured in April.

There are reasons for trepidation among stock investors as the war enters its third month.

The conflict could drag on for longer than is currently expected. Oil prices with Brent futures contracts from September through November have all started to rise, moving above $90 in just over the past week. Although that means traders still expect the price of oil to drift downward in the coming months, crude is increasingly expected to stay elevated for longer, weighing on the economy. The government’s bond market also shows signs of lingering inflation risks stemming from the war, analysts have noted.

Many investors have also expressed a lack of conviction in the current rally, which is evident in the way investors are trading. Stock market trading volumes have been subdued through April, with some investors saying they have turned to the derivatives market to place bets on the market going higher, allowing them to profit if the rally continues but limit losses if the market falls again.

“As long as the economy continues to grow and companies are able to grow earnings, we can see higher stock prices even in the face of higher energy prices and inflation,” said Chris Zaccarelli, chief investment officer at Northlight Asset Management. “However, the longer the war drags on, the more investors will grow nervous and we could see some pullbacks as fears ebb and flow.”

Over the past year, Jerome H. Powell has frequently said that the Federal Reserve faced “no risk-free paths” as it confronted a series of economic shocks that simultaneously lifted inflation while denting growth.

The same could be said for his momentous decision to stay on at the Fed as a governor after his term as Fed chair ends May 15.

In choosing to stay, Mr. Powell used the one tool of leverage he had left to push back on an administration that has aggressively attacked the central bank for its refusal to bend to the president’s demands for lower interest rates. Unless another Fed governor departs, President Trump will not have another vacancy to fill until Mr. Powell’s term ends in January 2028, stymieing the president’s plans to get more of his supporters on the powerful board of governors.

The move, which Mr. Powell announced on Wednesday at his final news conference after eight years as chair, drew an immediate rebuke from the administration. Mr. Trump quipped that Mr. Powell was staying because “he can’t get a job anywhere else — nobody wants him.” Scott Bessent, the Treasury secretary, called Mr. Powell’s decision a “violation of all Federal Reserve norms.”

On Thursday, Mr. Trump seemed to soften his approach, saying during remarks at the White House that he did not care if Mr. Powell stayed on and only was concerned about getting his Mr. Warsh into the top job.

The question now is whether Mr. Powell’s continued presence will further inflame tensions between the administration and the central bank, leading to even more intense attacks that will keep the institution on the defensive. Weeks before Mr. Powell announced his decision, Mr. Trump threatened to fire him if he did not resign after his term as chair ended.

“This could still go sideways, and if it does, some people will point to Powell staying as a provocation,” said Claudia Sahm, a former forecaster at the Fed who is now the chief economist at New Century Advisors. “Stay or go, there are risks on either side of this.”

Mr. Powell made clear on Wednesday that he wanted nothing more than to leave the Fed. Yet he said he had “no choice” but to stay and guard against further encroachments on the institution where he has served for nearly 14 years, first as a governor and then as chair. The last time a chair whose term had expired stayed on as a governor was in 1948.

“I’m literally staying because of the actions that have been taken,” Mr. Powell said when asked about whether his decision would be viewed as a political act. “I have long planned to be retiring.”

The decision had nothing to do with Kevin M. Warsh, Mr. Trump’s pick to replace him as chair, Mr. Powell stressed on Wednesday.

He said he took Mr. Warsh at his word that he would stand up to political pressure from the president. Mr. Powell also vowed to keep a “low profile as a governor,” despite retaining a vote on decisions around rates and other policies.

William Dudley, who previously was the president of the Federal Reserve Bank of New York, said he expected Mr. Powell to stay relatively quiet and embrace a “one man, one vote” approach.

Mr. Powell spent much of his news conference explaining that his decision to stay rested on a belief that the central bank’s independence was fundamentally “at risk” amid a litany of legal threats that were far from over.

“These legal actions by the administration are unprecedented in our 113-year history, and there are ongoing threats of additional such actions,” he said. “I worry that these attacks are battering the institution and putting at risk the thing that really matters to the public, which is the ability to conduct monetary policy without taking into consideration political factors.”

Top of mind for Mr. Powell is a criminal investigation that the Justice Department began against the Fed regarding renovations to its headquarters in Washington and whether he lied to Congress about the plans. Federal prosecutors dropped the inquiry on Friday, but maintained that they could reopen it at any point. Jeanine Pirro, the U.S. attorney for the District of Columbia, said on Thursday that there was “no question” the Justice Department would appeal a federal judge’s recent ruling that quashed subpoenas issued to the central bank. For now, the Fed’s inspector general is looking into the renovation, an inquest that Mr. Powell requested in July.

“You’ve got billions of dollars in cost overruns on a very small project,” she said, adding that prosecutors would await the “decision” by the Fed’s internal watchdog and “based upon that decision we will then decide what we are going to do.”

Mr. Powell has long stipulated that he would not leave the Fed until the Justice Department’s investigation was “well and truly over, with finality and transparency.” But a mounting concern is whether Mr. Trump will now use the allegations leveled in the investigation to try to fire Mr. Powell, having already accused him of “incompetence” and questioned whether he committed fraud.

“There’s definitely a cost-benefit analysis one would think Powell engaged in, and the cost of staying is that it greatly increases the likelihood that there will be a for-cause removal case against him involving the renovations, which would be a novel litigation,” said Lev Menand, an associate professor at Columbia Law School.

A president can remove a Fed official only for cause, which legal experts interpret to mean gross misconduct or a dereliction of duty. The issue is being debated by the Supreme Court after the president’s attempt to fire Lisa D. Cook, a governor, in August.

Joseph Gagnon, a former senior member of the Fed staff who is now at the Peterson Institute for International Economics, said it was crucial for Ms. Cook to win that case. “If they let Trump fire governors at will, then there’s no more independent monetary policy,” he said.

If Mr. Trump or the Justice Department pursues any additional legal actions, “being on the inside is always better than being on the outside,” Scott Alvarez, who previously served as the Fed’s general counsel, said of Mr. Powell’s decision to stay.

Graham Steele, a longtime financial regulation lawyer and a former Treasury Department official, noted that there would be “strategic” advantages in doing so, such as “physical proximity, access to information and the institutional halo effect that come from being a sitting governor.”

For the time being, Mr. Powell’s continued presence at an institution that has gone through so much tumult in the past year and is now on the cusp of a major leadership transition is “symbolically really important,” said Jon Faust, a fellow at the Center for Financial Economics at Johns Hopkins University and a former senior adviser to the outgoing chair.

What perhaps will matter even more is when Mr. Powell decides to leave, Ms. Sahm said.

“It will mean so much when he says, ‘I’m ready to retire,’ because that will be a sign from someone who cares deeply about the institution that it’s going to be OK.”

— Tony Romm contributed reporting.