India, Nov. 5 -- The Republicans' rout in the midterms could reshape American politics and its engagement with the world

America has delivered a rebuke. Democrats have won both the House and the Senate, flipping at least seven Republican-held Senate seats, among them Texas, Ohio, Iowa and Kansas, which has not elected a Democratic senator in nearly a century. In the House, projections put their majority at 250-plus seats. Midterms usually punish the party in the White House. This was something larger: a referendum on one man.

Why did Trump's popularity slide? Start with the household budget. Voters wanted relief and got stubborn prices, with petrol topping $4 a gallon at points. Add the war with Iran, which Vice President JD Vance has h...