- President Trump has called for modest gun control measures following the shooting massacre in a Florida high school.
- Trump also has backed improved background checks, age restrictions to buy rifles, banning bump stocks and arming teachers.
- Some of those proposals have a better chance of getting through Congress than others.
President Donald Trump has backed some gun regulation changes to stop school shootings and thinks Congress is "finally" in a mood to take action.
Whether lawmakers can muster enough support to pass any bill on gun rules remains to be seen.
Trump started to call for modest gun-control measures following the shooting massacre of 17 people at a Florida high school last week. As the students from Marjory Stoneman Douglas High School pushed for tighter gun restrictions and families affected by school shootings tearfully urged the president to take some type of action , Trump publicly pushed for tweaks to gun rules.
"I will be strongly pushing Comprehensive Background Checks with an emphasis on Mental Health. Raise age to 21 and end sale of Bump Stocks! Congress is in a mood to finally do something on this issue - I hope!" the president tweeted on Thursday morning.
Trump, in his consideration of these measures, has tiptoed around the National Rifle Association, which supported him during the 2016 campaign. At an NRA convention in April, the president told the gun lobbying group: "You came through for me, and I am going to come through for you." He reiterated his support for the NRA in a tweet Thursday, calling its leadership and staff "Great American Patriots":
TRUMP NRA TWEET
At a school safety event with state officials later Thursday, the president said he told the NRA that the U.S. needs to "toughen" some gun rules. He also said he called lawmakers about strengthening background checks.
In an earlier string of tweets Thursday morning, Trump also reaffirmed his call to give guns to specially trained teachers in an effort to deter or shorten shootings.
Lawmakers have already introduced certain proposals Trump supports. Some of those policies have a better chance of passing Congress than others.
Bipartisan senators have already put forward a narrow bill to improve the existing background check system. Trump voiced his support for it this week.
The bill aims to make federal agencies better at following rules that require them to submit criminal convictions to the FBI, which could help stop high-risk individuals from getting guns. Last year, the Air Force said it had not submitted records that could have stopped the shooter who killed 26 people at a church in Sutherland Springs, Texas, from buying a gun.
The legislation crucially has support from Republican leadership: Senate Majority Whip John Cornyn , R-Texas, introduced it. Gun control advocate Sen. Christopher Murphy , D-Conn., is among the other senators who has signed on.
The measure could hit a snag in the House. While the chamber passed legislation to improve the background check system last year, it did so in tandem with a measure that would allow people with concealed carry permits in one state to equip a weapon nationwide.
Senate Democrats will not support concealed carry reciprocity. Conservatives may insist the gun-carrying language is in any bill to strengthen background checks, according to Politico .
Under current federal law, individuals must be 21 years old to buy handguns from licensed dealers. However, they can buy shotguns or rifles at age 18.
The 19-year-old Florida shooter legally bought an AR-15 style semi-automatic rifle. Samuel Zeif, an 18-year-old student who survived the shooting, made an impassioned plea to Trump on Wednesday, fighting back tears as he asked why he could legally buy a "weapon of war" at his age.
Trump and others are pushing to change the age to buy rifles to 21.
On Wednesday, Sen. Jeff Flake , R-Ariz., said he was "working with" Sen. Dianne Feinstein , D-Calif., on legislation to move the age to purchase a rifle for nonmilitary buyers to 21.
"A kid too young to buy a handgun should be too young to buy an AR-15," Flake wrote on Twitter.
At a CNN town hall on Wednesday night, Sen. Marco Rubio , R-Fla., also expressed support for the measure. Despite the backing from some senators, that proposal could also run into resistance.
Members of Republican Senate leadership have yet to back the plan. In addition, many House Republicans could oppose it.
On Tuesday, Trump signed a memorandum recommending that Attorney General Jeff Sessions propose a rule banning bump stocks . The tool can effectively make a semi-automatic rifle automatic.
The gunman who opened fire on a concert in Las Vegas last year, killing 58 people in the deadliest mass shooting in modern U.S. history, used bump stocks. The massacre prompted calls to outlaw the devices, but a bill to bump stocks gained little traction in Congress after the rampage. It remains to be seen whether the measure can gather any fresh momentum with Trump's support.
Any rule crafted by the Justice Department could face challenges in court.
Trump argued Thursday morning that "attacks would end" if trained teachers had firearms at schools . Democrats and some Republicans would likely disagree with him.
Rubio broke with Trump on the proposal on Wednesday night.
"The notion that my kids are going to school with teachers that are armed with a weapon is not something that, quite frankly, I'm comfortable with," the Florida Republican said.
WATCH: Trump meets with students to discuss gun violence
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