Story highlights

Donald Trump said President Barack Obama "should step down" over his approach to the massacre

Sen. Chris Murphy blamed Congress for failing to enact gun control laws

Washington CNN  — 

Within hours, the Orlando mass shooting at a gay nightclub set off renewed political debates – with Democrats calling for gun control and Republicans blasting “radical Islamic terrorism.”

At least 50 people were killed and 53 more wounded Sunday, making it the deadliest mass shooting in American history.

Each side called those causes critical to preventing future shootings – but there are no signs that the dynamics in Congress have changed, leaving measures like new gun laws no path forward.

Late Sunday afternoon Donald Trump, the presumptive Republican presidential nominee, said President Barack Obama was far too timid in his White House appearance. Trump issued his first call in the campaign for Obama to step down from the presidency and challenged presumptive Democratic nominee Hillary Clinton to ratchet up her language about terror threats.

“President Obama disgracefully refused to even say the words ‘Radical Islam,’” Trump said in the statement. “For that reason alone, he should step down. If Hillary Clinton, after this attack, still cannot say the two words ‘Radical Islam’ she should get out of this race for the Presidency.”

Trump’s campaign is also pivoting the focus of a scheduled speech in New Hampshire on Monday. The speech will no longer focus on what Trump has called a litany of scandals involving Bill and Hillary Clinton. Now, according to the Trump campaign statement, it will “address this terrorist attack, immigration, and national security.”

Trump tweeted earlier Sunday: “Horrific incident in FL. Praying for all the victims & their families. When will this stop? When will we get tough, smart & vigilant?”

That approach stood in stark contrast with Sen. Chris Murphy, D-Connecticut, who said blame for mass shootings lies with Congress for its failure to enact stricter gun control measures.

“Congress has become complicit in these murders by its total, unconscionable deafening silence,” he said in a statement. “This doesn’t have to happen, but this epidemic will continue without end if Congress continues to sit on its hands and do nothing – again.”

Vermont Sen. Bernie Sanders, a Democratic presidential contender, offered similar comments on NBC’s “Meet the Press.”

“We should not be selling automatic weapons which are designed to kill people,” Sanders said. “We have got to do everything that we can on top of that to make sure that guns do not fall into the hands of people who should not have them, criminals, people who are mentally ill. So that struggles continues.”

After the shooting, Hillary Clinton got an endorsement from a Republican – former South Dakota Sen. Larry Pressler, who left office in 1997 after three terms – because of her position on gun control.

“Secretary Clinton would be able to handle such explosive situations which are terrorist inspired much better than Donald Trump,” Pressler said in a statement. “She has experience and is anti-(National Rifle Association) – and remember that these domestic terrorists also buy automatic weapons … Unfortunately the Republican candidate Trump has pledged publicly total cooperation with the NRA.”

Debate is over language and gun control proposals are likely to persist, as Sunday’s events demonstrated.

The businessman’s social media director, Dan Scavino, criticized President Barack Obama’s refusal to use the phrase “radical Islamic terrorism” in his condemnations of previous mass shootings.

“Will only get worse in America, when our POTUS can’t say, or recognize those 3 very words-RADICAL ISLAMIC TERRORISM,” he tweeted.

Alabama Sen. Jeff Sessions, a Republican, offered a similar take on “Fox News Sunday,” warning that he expects more attacks.

“More of these attacks are coming. It’s a real part of the threat that we face and if we can’t address it openly and directly, and say directly that there is an extremist element within Islam, that’s dangerous to the world and has to be confronted,” Sessions said.