Military exchanges between the United States and Iran reignited on Aug. 30 and 31. US forces struck two launchers on Larak Island at the mouth of the Strait of Hormuz, and Iran responded with missile launches. It was the first confirmed American strike on Iran since late July, and the conflict that began in late February entered its sixth month.

Markets reacted at once. On Aug. 31 Brent futures rose $2.37, or 2.69 percent, to $90.47 a barrel, while West Texas Intermediate gained $2, or 2.4 percent, to $85.40. Renewed supply-disruption fears, compounded by low US strategic reserve levels, drove the move.

What set it off again

The two sides had entered a truce last month with a memorandum on ending hostilities, but talks over passage through the Strait of Hormuz stalled. With no common ground on transit conditions and inspection procedures, military installations on islands near the strait became targets once more.

Larak Island is a small island at the Iranian side of the strait's entrance, close to the shipping lanes that run through it. That position has made it a military focal point whenever the transit question resurfaces.

The Kharg Island variable

Trump posted a one-line message on social media referring to Kharg Island, without elaboration. The White House offered no specific explanation of what the post meant.

Kharg Island is an oil export terminal off Iran's southwestern coast through which roughly 90 percent of the country's crude exports pass. Its loading capacity is estimated at 7 million barrels a day and its storage capacity at about 30 million barrels. Energy market analysts generally hold that any actual disruption there would be of a different order from a strike on Larak.

What has been confirmed so far, however, is the social media post and the market's response to it. No operational plan or timing has been disclosed, and this paper does not treat the wording of a post as equivalent to a policy announcement.

Fuel prices were already climbing

In the United States, the average price of gasoline topped $4 a gallon on some days in August for the first time. Peak summer demand, refining margins and Middle East supply uncertainty combined to produce it. The renewed exchanges added pressure to prices that were already elevated.

European equities closed lower alongside the oil move. In Asia, semiconductor-related shares rose on company-specific news even as broader indices weakened, showing that the oil shock is absorbed unevenly across sectors.

The path to Korea's economy

Korea imports nearly all of its crude and leans heavily on Middle Eastern supply. State research institutes have repeatedly estimated the effect of a $10-per-barrel rise on consumer prices and the trade balance, and the estimates generally point toward higher inflation and a weaker current account.

If the exchange rate moves in the same direction, the burden compounds. When a weaker won overlaps with rising crude, import prices climb twice over. How long this phase lasts depends on whether the Hormuz talks resume, so firm conclusions are premature.

For the Sinophone community in Korea

For Chinese-Korean merchants in Incheon and Seoul who handle imported foodstuffs and household goods, crude prices and ocean freight feed straight into costs. When transit through the strait becomes unstable, insurance premiums and freight rates on Middle East routes move first.

Remittance conditions are affected too. If an oil spike stokes risk aversion, emerging-market currencies wobble with it, raising the real burden on families sending money home. That is the reasoning behind advice to stagger non-urgent transfers.

A third view: six months of learning

Over six months of this conflict, markets have learned two things. One is that physical crude supply has not actually been cut off. The other is that prices react every time regardless. The first has capped rallies; the second has put a floor under them.

This paper does not read the renewed exchanges as a win or loss for either side. The verifiable facts are the strike locations, the price figures, and the fact that talks are frozen. To say more, one would need to know what is actually on the Hormuz negotiating table. What readers need is not a forecast but a list of which numbers to watch.