WHEN I TOLD a friend I was writing a column about vermouth, she responded with surprise. “But vermouth isn’t wine!” she replied. In fact, this venerable, spice-infused, fortified drink is made from wine. Christopher Tracy, winemaker of Channing Daughters Winery in Bridgehampton, N.Y., told me that quite a few visitors to his tasting room were taken aback by this news as well. “But they love it when they taste it,” he said.

Mr. Tracy is one of a new breed of American vermouth makers producing novel and exciting versions of...