The rush of UK citizens seeking Irish nationality in the wake of the Brexit referendum has caused concern to many.

Writing in this paper, Christopher Kissane and David Kenny note that many may bristle at the use of Irish citizenship as a badge of convenience for those merely wishing to maintain the status of EU citizens.

However, they move to dismiss these concerns as a “misunderstanding of the expansive nature and history of Irish nationhood”.

Citizenship is fundamental to the collective self-government involved in democracy. The welfare state is also very dependent on the idea of citizenship.

Social welfare systems involve taxpayers undertaking to economically support people they do not know. Such an undertaking is impossible without the sense of shared identity and solidarity that citizenship provides.

The value and sustainability of this sense of solidarity risks being undermined if citizenship is granted to large numbers of people with little real connection to the State.

The limited degree of connection to Ireland required by our citizenship laws has been in place for some time.

However, there are many instances where legal rights are granted on the expectation that they would not be widely taken up.

EU free movement rights are a good example of a situation where political and legal problems have been caused by large-scale take up of rights that had previously been used on a smaller scale.

Free movement

As the UK’s decision to leave the EU shows, the large-scale use by citizens of these states of free movement rights made those more controversial than before. It has also put pressure on the rights that go with free movement.

The European Court of Justice has, for example, since late 2014, strengthened restrictions on the ability of EU citizens to access the welfare state in other EU states.

Kissane and Kenny argue that voting rights for the Irish abroad must be strengthened.

However, the fact that so many people born abroad are entitled to Irish citizenship is one of the key reasons why the voting rights of the Irish abroad have to remain limited.

Following the approach of countries that allow all citizens to vote by post from abroad would risk subjecting those living in Ireland to the political decisions of those overseas.

The core of Kissane and Kenny’s argument is that extending citizenship to those with limited connection to Ireland would represent a welcome “openness” and “embrace an expansive and inclusive Irish citizenship”.

This does not do justice to the reality that, as with most choices between worthy goals, there is a trade-off.

Balance

At the same time, one that is too expansive could devalue a concept that is at the core of our democracy and the solidarity that sustains the welfare state, as well as leading the State into making promises it may struggle to keep.

The Constitution’s provisions on citizenship stress a “special affinity with people of Irish ancestry living abroad who share its cultural identity and heritage”, not with anyone who happens to have an Irish grandparent.

There are many ways short of citizenship that the State can nurture this “special affinity”.

The UK has a programme allowing those with ancestral connections to Britain to live and work in the UK for up to five years with a chance to apply for permanent residency thereafter.

Indeed, marrying an Irish person may involve a much more significant connection to the State than having an Irish grandparent but the law as it stands requires the non-Irish spouse to live in Ireland in order to obtain citizenship.

A generous citizenship system is a sign of a healthy, welcoming approach to the world.

However, Irish citizenship rules were almost certainly designed on the assumption that there would never be a need for large numbers of descendents of Irish emigrants to obtain Irish nationality.

It is important to honour and nourish links with those who have a genuine link and commitment to Ireland. Current rules do not achieve this goal.

They allow large numbers of people from wealthy countries, who may have very limited links to Ireland, to use Irish citizenship as a flag of convenience.

If the law treats citizenship in this cavalier way it becomes more difficult to expect those citizens resident in Ireland to treat citizenship seriously as a source of solidarity and duty to society.

Ronan McCrea is a senior lecturer in law at University College London