So here are my three passports, showing signs of age (on two of the passports themselves, and in the photograph on the third).
I must say I'm fundamentally a bit libertarian about nationalities. It seems to me that if I want citizenship of a country, and they are prepared to grant it to me, it's not really anyone's business whether I am also a citizen of anywhere else. I'm glad that the UK, Ireland and Belgium are relaxed about this. And if the UK ever does leave the EU, I have not one but two backups.