'Scared to death': Many Republicans are silently shuddering at Trump's VP pick

Many powerful Republicans are horrified and frustrated by Donald Trump's choice of running mate in the upcoming presidential election, according to a new report.

Sen. J.D. Vance's isolationist views both alarm and infuriate hawkish Republicans who fear the 39-year-old will destroy the Republican Party's longtime foreign policy consensus, Politico reported Wednesday.

"Trump didn’t just select a running mate here – he doused political kerosene on the raging Republican fire over foreign policy," writes columnist Jonathan Martin. "While toeing the party line and praising Vance in their public comments, in private the interventionists ranged from horrified to merely alarmed that one of the loudest critics of aiding Ukraine could soon be first in line for the presidency."

One influential Republican member of Congress told Martin, “I’m scared to death.”

Rep. Ken Calvert (R-CA), Defense Appropriations Subcommittee chair, reportedly raised concerns about Russia's invasion, telling an associate, “The Ukrainians better hurry up and win.”

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Trump's decision, which represents a victory for his eldest son who lobbied hard for Vance, showcases the lack of influence Republican infighters such Sen. Mitch McConnell (R-KY) have on the former president, Martin writes.

"[McConnell] had little to say about the Vance pick, only raising an eyebrow when I asked him about it immediately after it became public and declining to speak any further," Martin writes.

"McConnell is a party man first and was unwilling to distract from the unity of the week."

Many Republicans presented a united front in public, but Martin reports a swift shift in mood behind closed doors.