Following Mattis: More in the GOP frown on Trump’s tone

Demonstrators protest Thursday, June 4, 2020, on the West Front of the U.S. Capitol in Washington, over the death of George Floyd, a black man who was in police custody in Minneapolis. Floyd died after being restrained by Minneapolis police officers. (AP Photo/Alex Brandon)

Sen. Mitt Romney, R-Utah, leaves a Republican luncheon on Capitol Hill in Washington, Thursday, June 4, 2020. (AP Photo/Susan Walsh)

FILE - In this March 19, 2020, file photo Sen. Lisa Murkowski, R-Alaska, talks with reporters following a Republican policy lunch on Capitol Hill in Washington. Murkowski acknowledged Thursday, June 4, that she’s “struggling” over whether she can support President Donald Trump given his handling of the virus and race crises shaking the United States. (AP Photo/Susan Walsh, File)

President Donald Trump walks past police in Lafayette Park after he visited outside St. John’s Church across from the White House Monday, June 1, 2020, in Washington. Part of the church was set on fire during protests on Sunday night. (AP Photo/Patrick Semansky)

WASHINGTON — President Donald Trump’s inability to unify the nation at a time of grave unrest is testing his uneasy alliance with mainstream Republicans, some emboldened by Gen. James Mattis’ plea for a leader who lives up to the U.S. ideals of a more perfect union.