We can all take action to avoid more attacks like the Pittsburgh synagogue shooting

We know that hate speech can lead to hate actions. The person who fires the gun is responsible for the murder, but the person who unleashes the hate that triggered that response is also guilty

According to Donald Trump, the answer to preventing attacks on synagogues – or any other place of public gathering – seems to be having armed guards inside the building. A better solution would perhaps be not having armed killers outside them.

Of course, we cannot prevent a deranged individual trying to act murderously once he or she has lost all sense of reason, but we can make it much less likely that they get to that stage.

Firstly, by not allowing citizens to have virtually unfettered access to weaponry. The ability for individuals in the United States to easily procure guns means that mass shootings are now regular occurrences, whether in schools, shopping malls or places of worship. Here in the UK we may have had occasional incidents – such as the Hungerford shootings in 1987 – but there is a clear correlation between gun control in the UK and the paucity of such occurrences.

Secondly, by reducing the toxic level of political and social discourse, in which opponents are painted as not only being wrong, but intrinsically evil people who deserve punishment. It is not new: when Henry II reportedly said “Who will rid me of this turbulent priest?”, he may have been asking it rhetorically, but it led four knights to take it literally and ride off to Canterbury to assassinate Thomas Becket.

But whereas that episode has served as a warning for centuries to those in power to guard their tongue, such reticence has disappeared today.

Trump is not the only person to retaliate against those with whom he disagrees with incendiary language, but he bears more responsibility than most because of his office. The great hope that the vitriol he used on the campaign trail would disappear once he became president has proved false.

But it is too easy to castigate Trump, and we in the UK need to look in the mirror just as much. Despite the cries of outrage when Jo Cox was murdered, some MPs seem to have totally forgotten their pious words at the time and engage in the poisonous terms that they condemned in others. The advice to Theresa May to bring her own noose to the 1922 meeting of backbench MPs last week attracted criticism, but no one has felt brave enough to out the person concerned.

We know that hate speech can lead to hate actions. It is that simple. Not in everyone, but in enough people who may have other issues – grudges, depression, mental illness, a warped desire for glory, radicalisation – to make it highly dangerous. The person who fires the gun is responsible for the murder, but the person who unleashes the hate that triggered that response is also guilty.

Ordinary people have a role to play too. The Pittsburgh suspect had expressed not only his hatred of Jews, but his intention to act upon it. If we notice people we know – family, friends, work colleagues or those on social media – voicing hate and making alarming statements, we have a civic duty to alert the police.

If we saw a man at night placing a ladder against a house, we would assume a burglary was about to happen and call 999. This is no different, and it would be tragic for those who see the next warning signs but do not do anything about it, to say afterwards “if only, I had...” following another killing spree.

The Pittsburgh attack was doubly shocking, both in the death toll, and the fact that it was not at a high profile venue or event, but a local place of worship. The victims were not famous, but Mr and Mrs Ordinary. It was an attack on anyone and everyone, and that makes it even more chilling. The good news is that we have potential solutions, and the big question is whether we will avail ourselves of them.

Dr Jonathan Romain is rabbi of Maidenhead Synagogue