Rep. Darrell Issa personally apologized for cutting off Cummings' mic in a House hearing.
The former national security adviser says Russia is "vulnerable" to sanctions.
Wayne LaPierre said the NRA "will not go quietly into the night."
Sanders said he had not decided if he would run as a Democrat or independent.
The White House on Thursday moved to impose economic sanctions and visa restrictions.
A new poll says only 30 percent of Arizonans approve of McCain.
“Ignoring threats to our national security is the Obama doctrine,” the ex-ambassador said.
The Russian foreign minister called the decision to impose sanctions "unconstructive."
'You don’t really have to talk about it. If you talk about it too much, you lose your credibility. And you have to be taken seriously,” said Marine Corps Gen. Jim Jones, who served as Obama’s national security adviser for two years.
“I don’t know what her political future is, whether she’s going to run,” he said.