In June 2016, Omar Mateen walked into the LGBTI nightclub Pulse and opened fire on patrons as they danced and drank with their friends. The attack left 49 people dead and — notwithstanding US army massacres and attacks on Native Americans — was generally agreed to be the deadliest mass shooting in US history.

Overnight, just over 15 months later, Mateen’s grim record was surpassed by Stephen Paddock, a 64-year-old who perched high in the Las Vegas Mandalay Bay Resort and, with at least 20 rifles by his side, unloaded round after round into a crowd at a country music festival. At least 59 people are dead and an astonishing 500-plus injured.

As ever, a mass shooting will bring America’s gun violence issue back to the arena of federal politics. It comes at a time when pro-gun groups like the National Rifle Association are driving the national agenda and scrambling to cash in on a friendly Congress and one of the most pro-gun administrations they’ve ever seen.

NRA’s investment pays quick dividend

With the rise of Donald Trump throwing up everything from questions of foreign collusion to the threat of nuclear war with North Korea, little attention has been paid to the fact the current administration is one of the most pro-gun Washington regimes in recent history.

During the election, the NRA spent a record $36 million, digging in behind Trump, and launching attacks against Hillary Clinton. Since then, the President has been open about where his loyalties lie, becoming the first US leader since Ronald Reagan to speak at the NRA’s annual meeting. “You came through for me and I am going to come through for you,” Trump vowed.

Believe it or not, beyond the NRA is a constellation of smaller, even more ardently pro-gun lobby groups. Since the election they’ve switched from defence to offence, turning energy away from the executive orders of the Obama era and focusing instead on hesitant Republicans, goading them to turn their control of Congress and the presidency into new gun laws.

There have been a number of small, early wins, including removing tens of thousands of names from a national background-check database.

The most important, though, has been the appointment of Neil Gorsuch to the Supreme Court, a move the NRA declared to be “outstanding”. There have also been scores of appointments to lower courts that have pleased gun groups.

“We can’t complain at all,” Alan Gottlieb of the Second Amendment Foundation told me earlier in the year.

Groups like this now see Republican sluggishness and a bloated congressional agenda as their main foes to overcome.

The big fight now: a nationwide weakening of concealed-carry laws

With a Senate filibuster the only thing between the NRA and whatever the hell it wants, the first major test of Trump’s gun agenda is yet run its course.

Every state in the US allows residents to carry a concealed weapon but there is a significant difference on what kind of permit you need to be able to do so. While some states give law enforcement discretion to deny permit applications for a range of reasons, just under a dozen require no permit at all. (Nevada, the state where last night’s mass shooting took place, is a middle-ground state; a permit is required but you’re pretty much guaranteed to get one).

You would think this states’-rights approach would suit the gun lobby while also satisfying right-wingers who want the federal government to back off. It doesn’t.

Before Congress is a bill that would force states to accept the standards used by other states. If passed, states with tough permit laws would not be able to stop people from other states carrying their concealed weapon if they had a permit form their home state. This would effectively mean states with the weakest permit systems (i.e. no checks or permits at all) would become the national standard.

Pro-gun groups portray this as a commonsense reform to stop someone who has a permit being arrested when they go back across state lines to visit Ma and Pa. Gun-violence prevention groups see it as an oppressive federal measure that would increase the presence of guns in public, and lead to more deaths.

The NRA has said that passing concealed-carry laws is a top priority and one bill in Congress already has over 200 sponsors.

Silencers about to get loud

Even before this week, silencers were set to land on the agenda, possibly within days. The US government has traditionally limited access to the devices but laws before Congress would make them easier to get, something law enforcement agencies are not too keen on, given the fact they enable ambush-style killings.

Needless to say, it’s all a matter of public health according to pro-gun groups, who just want to protect shooters’ ears.

The issue is even more pertinent now given the Las Vegas mass murderer would have presumably been able to inflict more damage had he been able to mask the sound of his fire. With Hillary Clinton tweeting concerns to that effect this morning, this one is going to get hyper-political.

Gun control groups cling to hope

In the wake of Trump’s election, some gun control groups like the Coalition to Stop Gun Violence insist that the US has changed since the Sandy Hook Elementary School shooting in Newtown, Connecticut, in 2012. They argue that state ballot initiatives and some gubernatorial results prove this: Hillary Clinton won just 52% of the vote in Washington state, for instance, but a ballot initiative proposing temporary firearm restrictions on at-risk people won nearly 70% support.

Yet even after Newtown, Congress failed to pass mild new measures. The belief that “the only way to stop a bad guy with a gun is a good guy with a gun” remains widespread.

With Republicans in control of the House and Senate, gun control at the federal level will remain focused on damage control for the near future.