The murder of the pro-EU MP Jo Cox just as the UK referendum entered its final week was a shocking reminder of how political passions can so easily be perverted for evil ends.
While the assailant was clearly deranged and not at all representative of the Leave campaign it is difficult to avoid the conclusion that the increasingly hysterical nature of the debate may well have been a contributory factor.
It is not just in the UK that political campaigners need to take a step back and ask themselves if they are contributing to an erosion of respect for democratic political values that can lead to such dire consequences.
A wave of cynicism and bitterness has infected political debate right across the democratic world as evidenced by the campaigning style of Donald Trump in the US and various populist leaders across Europe.
We are not immune to the virus in this country either. The harassment of some TDs during the last government's term was sinister. Frank Feighan has spoken publicly and others privately about the kind of intimidation they were subjected to in their constituencies in recent years.
One of the fundamental problems across the democratic world is the growing appeal of populism of the left and right which seeks to simplify almost all issues to a clash between the interests of ordinary people and a “corrupt elite”.
A fascinating study dealing with the challenge populism poses to the EU, published by the Carnegie Institute this week, said populism is essentially illiberal because it rejects democratic checks and balances and has a conception of the will of the people that leaves no room for pluralism or deliberation.
Ritualistic outrage
One of the positive aspects of the political scene that has emerged as a result of our inconclusive general election is that the level of ritualistic outrage and indignation in the Dáil appears to have calmed down. There has been more considered debate and discussion of issues than happened when governments had a secure majority.
That process has been helped by the fact that political debate is no longer totally focused on spending cuts but on possible solutions to a variety of problems. Whether that would survive if we are plunged into another economic crisis as a result of a British vote to leave the EU is another question.
The likely consequences of a British exit has prompted an unprecedented level of intervention by Irish political leaders in the affairs of our near neighbours. The Taoiseach and an array of Ministers have been doing their best to mobilise voters with Irish connections in Britain to vote in favour of remaining in the EU.
Fianna Fáil leader Micheál Martin and Labour leader Brendan Howlin have been campaigning in Britain too. With opinion polls showing the Leave campaign in the lead it is clear every vote will count.
More than 800,000 self-identified Irish voters live in England and there are many more with Irish connections. If a significant number of them are persuaded to vote to remain in the EU it could prove the most decisive Irish intervention in British politics since Parnell instructed the Irish in Britain to back the Conservatives in 1885 or John Redmond asked them to vote Liberal in 1910.
This time around, the perceived best interests of Irish nationalism is keeping our neighbours with us in the EU not just for practical reasons to do with the economy, Northern Ireland and the common travel area but because of the deep attachment between the two countries has never been as strong.
There is no guarantee that the Irish-linked element of the electorate in Britain will vote to remain in the EU. An RTÉ television interview with Irish emigrants at the first round of the Connacht championship between Mayo and London in Ruislip was an eye-opener. A fan wearing a GAA county jersey told the interviewer he had been in England since the age of 15 and he was voting to leave the EU because all the immigrants were coming over to the UK and taking jobs. The interview was a salutary reminder of how referendums can be won and lost.
Referendums are calculated to fuel the irrational side of political debate and encourage mob rule. Hitler used the referendum device to dismantle the democratic institutions of Weimar Germany. That is why the Germans have avoided referendums since the restoration of democracy in that country after the second World War.
Fears
In this country we have seen referendums used and abused by various groups who have sometimes managed to persuade people to vote on the basis of fears that had nothing to do with the issue in question. EU treaties were twice rejected on spurious grounds only for the electorate to sheepishly revisit the issues.
Referendums so often involve logic going out the window. For instance, the stance taken by the Democratic Unionist Party in the North to back the Leave campaign is likely to hasten the break-up of the UK with incalculable consequences for Northern Ireland.
Irish rugby captain and Armagh farmer Rory Best has shown a capacity to lead off the field by urging his community to vote to remain in the EU but, going by the polls, it looks as if the majority of the unionist community will vote to leave, regardless of the consequences.
It is some irony that on the centenary of 1916, Irish nationalist parties of all persuasions want the UK to remain closely linked to us while the biggest party of Irish unionism is committed to a course that would damage the economic interests of Northern Ireland and undermine its constitutional position in the longer run.