Unbowed, Trump fired a searing warning yesterday via Twitter to fellow Republicans carping about his proposal. A majority of his supporters, he tweeted, would vote for him if he left the party and ran as an independent.
The crossfire between Trump and frustrated Republicans became a media blur the day after the billionaire businessman announced his plan.
Beleaguered 2016 rivals condemned his proposal and complained that his divisive positions were dominating attention in the crowded Republican contest. Party elders, meanwhile, warned that too much criticism might indeed push him to launch a third-party bid that could hand the presidential election to the Democrats.
"This is not conservatism," declared House Speaker Paul Ryan, the Republican Party's top elected leader. "What was proposed yesterday is not what this party stands for. And more importantly, it's not what this country stands for."
Meanwhile, Secretary of State John Kerry today said that Trump's rhetoric is complicating US diplomacy.
"I stay out of politics," he told reporters in Paris. "But on this one I have to say something because it involves my job, it involves our country."
Kerry said that "what Mr Trump has said runs contrary" to US values of religious tolerance "and makes our job of reaching out to people and sharing America just that much more complicated and that much more difficult. And that's about as diplomatic as I can be about it."
One by one, Republican officials across the country lashed out at Trump's plan, which calls for a "total and complete shutdown of Muslims entering the United States" to help quell the threat of terrorism.
The Republican Party, said Jeb Bush adviser Ana Navarro, is stuck between "a rock and a jerk" less than eight weeks before the first primary-season votes are cast in Iowa.
