Oil prices moved above $100 a barrel for the first time since July as renewed exchanges in the Iran war disrupted energy markets. Brent crude approached triple-digit territory and natural gas prices reached three-year highs after Iran attacked U.S. bases, following the destruction of several Iranian oil tankers, while Iran-backed Houthis targeted energy facilities and cities in Saudi Arabia. Shipping through the Strait of Hormuz again slowed sharply as winter approached. Washington also imposed bans on some Canadian alcoholic beverages, motorcycles and dairy products after Canada retaliated dollar-for-dollar against U.S. tariffs. President Donald Trump said Bombardier would lose access to the U.S. market unless it began manufacturing there. The escalation has raised concern in Europe and Asia that broader U.S. tariffs may follow. Higher energy costs and geopolitical tensions pushed up long-term borrowing rates ahead of expected interest-rate increases by the European Central Bank, the Bank of Japan and possibly the U.S. Federal Reserve. Wall Street stocks ended lower Tuesday, while investors awaited U.S. inflation reports due Thursday and Friday. OpenAI's GPT-6 Astra gave software shares a boost, while chip stocks rose again in Asia. Markets also awaited details of Treasury Secretary Scott Bessent's first bond buyback, scheduled for Thursday and reportedly intended to cool the bond market's fever, although Treasury yields remained as high as when the plan was announced last month. The yen traded near seven-month highs, supported by expectations of a Bank of Japan rate increase and reports that Japanese investors were shifting money into higher-yielding domestic government bonds. Japan's currency was up 4% for the month, but speculative short positions remained substantial. China reported a marked August increase in subdued consumer and producer prices, mainly because of higher energy costs. The day's scheduled event included a U.S. 10-year note auction at 1 p.m. EDT. The column also directed readers to coverage of the global economy's resilience and the market effects of oil's resurgence and Washington's import bans.