[Fr Paul Keane] I know that we should not cry over spilt milk. But such good milk has been spilt! For those of us who voted in the referendum to remain, it is hard to look beyond the mess that lies before us: the break-up of the United Kingdom, economic uncertainty, loss of jobs to countries within the EU, and a seeming increase in racism.Perhaps these are just the growing pains or after-tremors of a destiny-altering but liberating decision. Yes, our holidays this summer will be much more expensive, but give it time and everything will work out for the best. I hope so. But I doubt it. Those who led the Leave campaign promised lower migration levels, more money for the NHS and greater sovereignty. Unprepared, I suspect, for their victory, they have already backtracked on their first two promises and the third is a questionable gain.Some Catholics have argued that the principal of subsidiarity, enshrined in papal teaching, was a decisive reason for voting Leave in order to extricate ourselves from an interfering and unaccountable Brussels’ bureaucracy. It is true, as Pope Francis has commented, that the EU’s systems need reform, but does subsidiarity, by its very nature, bring into question membership of the EU?Subsidiarity is praised in Leo XIII’s encyclical Rerum Novarum and then again in Pius XI’s Quadragesimo Anno. In the latter Pope Pius writes: "It is a fundamental principle of social philosophy, fixed and unchangeable, that one should not withdraw from individuals and commit to the community what they can accomplish by their own enterprise and industry."So subsidiarity is about defending individuals and families from unwarranted intrusions by the state. It does not, in itself, consider the sovereignty of nation states in supra-national organizations.However, at all levels, interventions are sometimes warranted, such as when a local authority intervenes to protect a child within a negligent family; Parliament enacts laws for the benefit of UK citizens; or the EU draws up regulations, having first consulted national governments, which ensure, for example, standards of production or European-wide health care. Subsidiarity is a good, but not an absolute one. Sometimes others know best or more can be achieved by co-operating at a national or continental level. Being a member of the EU involves compromising on absolute sovereignty but for the sake of greater prosperity and peace. We are stronger together.Unity was Our Lord’s prayer the night before He died. And anyway is absolute sovereignty in a globalised world desirable? Every country is vulnerable to world crises but when united with others – such as in the EU or NATO – we are better able to endure them.Peace! We have not celebrated enough this achievement of Europe. Our continent was the cause of two world wars, its countries at each other’s throats. After 1945, many states suffered under totalitarian regimes but in the name of peace, through trade, and shaped by the Catholic values of the founders of the Common Market, Europe grew stronger and more united.There have been mistakes but these can be overcome. Our referendum, however, has removed us from the gatherings of European heads where decisions will be made, decisions which will affect us no less for our absence, but which we shall not have shaped. We did not begin either of the two world wars but we fought in them because Europe will always be at the heart of our future. Surely it is better to be a shaper of that future rather than a spectator?Like successive governments, both the Leave and Remain campaigns failed to be honest about immigration. Certain regions have high number of immigrants. Their services have not received the extra support they need and so other regions, with hardly any immigrants, fear they will suffer the same fate in turn. Therefore, it is not surprising that immigration has been the single most important issue in the referendum. Yet in our contemporary world we gain from immigration. Immigrants grow our economy: unemployment is now at a ten-year low even though Eastern Europeans can travel to and work with ease in the UK. They are mostly hard-working Christians. They improve the lot of their families abroad while serving us at home.I know that the majority have spoken but I wish that it was possible to have another referendum and argue more truthfully the case for membership of the European Union. I wish this because our decision to reject the EU is too important to be decided by a small majority; the promises of the Leave Campaign are proving false; the United Kingdom is going to break apart; and seventy-five percent of those under-forty-five years old, who voted, voted to remain. We have denied the youngest the future they wished.Over the months and years to come, we shall have to tread very carefully; we have spilt an awful lot of milk.[Fr Paul Keane, a priest of Brentwood, is a Catholic Voices speaker]