LAS VEGAS—Republican presidential contenders clashed Tuesday over how to protect the country from a future terrorist attack and what role the U.S. should play on an increasingly tumultuous world stage.
The result was a policy focused debate that opened divisions—and sparked personal attacks—between the party’s top candidates over how far to go in monitoring Americans’ phone data, whether to deploy more U.S. troops to the Middle East and the merits of regime change.
The centerpiece of the showdown was the evolving feud between Sens. Ted Cruz of Texas and Marco Rubio of Florida, two leading contenders to be Donald Trump’s primary alternative. The two senators fought over data-collection, military spending, immigration and whether to topple Syrian President Bashar al-Assad.
While Mr. Trump remains the front-runner, the fight between Messrs. Cruz and Rubio intensified a long-standing split inside the GOP between conservative insurgents and more pragmatic Republicans, a power struggle that has dogged the party for years.