NRA President David Keene said he is aggressively preparing for "battle" with the White House and Congress over President Obama's gun control plan.
He also defended the new NRA ad calling Obama an "elitist hypocrite."
Keene criticized Obama's announcement Wednesday, surrounded by four children from around the U.S., for "using kids to advance an ideological agenda."
He expressed confidence that few measures would ultimately pass.
"It's going to be very tough for the president to accomplish some of these things, but that doesn't mean he can't do it if he really turns it on," Keene told ABC.
"All bets are off when a president really wants to go to war with you," the NRA president said, but "We're gonna be there and we're gonna fight it."
NRA members would hold accountable any politicians who "sell them out to some pie-in-the-sky scheme such as the president is proposing," he said.
The group launched a new "Stand and Fight" advocacy campaign Tuesday, opposing Obama's gun control measures, anchored by a controversial new TV ad.
The ad calls Obama an "elitist hypocrite" for sending his daughters to a private school with armed guards while being "skeptical" of armed security in all schools.
The White House blasted the ad as "repugnant and cowardly."
Keene isn't backing down, defending the ad last night:
"When the question is the protection of children, which is what this is all about… it's perfectly legitimate to ask why some should be protected and others should not be."
"We were talking about an elite class who criticizes others in their desire to be safe while making sure that they and their families and their children are always protected."
"We were not talking about the president's kids. We're not talking about the Secret Service protection [Obama's] children enjoy - they ought to have that wherever they go."
Keene also slammed Obama for using kids as "props," saying, "We didn't line them up on stage and pat them on the shoulder while we urge somebody to take our position."
Gun control: Time for tougher measures?