Oil is again above $100. And the markets are back on edge.
Prices rose after the United States Central Command (part of the Department of Defence) announced a naval blockade around Iranian ports. The goal is to halt Iranian oil exports and prohibit tolls in the Strait of Hormuz.
As a result of the higher supply disruption risk, US crude (West Texas Intermediate) surged 8% to $104.24 a barrel. Brent crude surged 7% to $102.29. This is the same benchmark that was near $70 before the war in late February, but soared to $119 at its peak. It had dropped to $95 ahead of peace talks. However, that relief has dissipated as the US-Iran peace talks failed.

The Strait is important because it transports one-fifth of the world's traded oil every day. Saudi Arabia, Iraq, the UAE, Kuwait, and Iran rely on it. Even if ships may sail through non-Iran ports, the risk to tankers has increased. Fewer ships. Higher insurance. Deliveries are slower.
The rise in oil prices triggers the fall of the markets.
S&P 500 futures declined 1%. Asian indexes dropped. The dollar strengthened. Risk currencies, including the Australian dollar and sterling, declined. US Treasury futures fell as markets braced for increasing inflationary pressure. Gold, which had surged prior to the war, dropped as investors took profits.
Analysts say the market has returned to pre-ceasefire circumstances, with the exception that the US is attempting to restrict up to 2 million barrels per day of Iranian-linked flows via Hormuz.The greater concern is not today's blockage, but what happens if strikes restart and energy infrastructure across the area is damaged.
That danger is what keeps oil prices above $100. And makes markets uneasy.