Mr. Pence accused Germany again of putting its own interests ahead of its neighbors’ and of giving Russia a possible tool to pressure the West.
“We can’t ensure the defense of the West if our allies are dependent on the East,” he said.
In her speech, Ms. Merkel said that Europe was buying Russian gas anyway, even if it arrived through a Ukrainian pipeline. Even during the Cold War, she said, “we imported large amounts of Russian gas. I don’t know why times should be so much worse today.”
“Do we want to make Russia only dependent on China? Is that our European interest?” she asked. “I don’t think so.”
Mr. Pence, for his part, said that the United States was committed to NATO, and he praised Mr. Trump for pushing allies to spend more on defense, for standing up to China and North Korea and for showing renewed American leadership in the world.
After both leaders had spoken, many observers came away struck by the difference in tone and reception.
“In contrast to Merkel’s visionary outward-looking speech that triggered warm applause, Mr. Pence delivered a stilted defense of Trump’s achievements to a skeptical audience,” said Amanda Sloat, a scholar with the Brookings Institution in Washington and a former official in the Obama administration.
Ms. Merkel even mocked the idea that German cars could be considered a “national security threat” by the United States, as American trade officials have asserted.
“If that is viewed as a security threat by the United States,” she said, “we are shocked.”
Declaring that BMW’s largest plant was now not in Bavaria but in South Carolina, she added, “We are proud of our cars, and so we should be.”