Americans in large numbers want the U.S. to reduce its role in world affairs even as a showdown with Russia over Ukraine preoccupies Washington, a Wall Street Journal/NBC News poll finds.

In a marked change from past decades, nearly half of those surveyed want the U.S. to be less active on the global stage, with fewer than one-fifth calling for more active engagement—an anti-interventionist current that sweeps across party lines.

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