WASHINGTON — Russia has secretly deployed a new cruise missile despite complaints from American officials that it violates a landmark arms control treaty that helped seal the end of the Cold War, administration officials say.
The move presents a major challenge for President Trump, who has vowed to improve relations with President Vladimir V. Putin of Russia and to pursue future arms accords.
The new Russian missile deployment also comes as the Trump administration is struggling to fill key policy positions at the State Department and the Pentagon — and to settle on a permanent replacement for Michael T. Flynn, the national security adviser who resigned late Monday. Mr. Flynn stepped down after it was revealed that he had misled the vice president and other officials over conversations with Moscow’s ambassador to Washington.
The ground-launched cruise missile at the center of American concerns is one that the Obama administration said …
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