The Romans called the Mediterranean mare nostrum. The Greeks must have had a similar expression. They are all gone. Now the Mediterranean is mare meum.

Addendum (April 7, 2018)

Having come across this piece entirely by chance, I shudder. The Mediterranean of this day and age is turning into a deathtrap for so many Africans and Asians. Migrants heading for Europe are attempting to cross it in ever-larger numbers, and they will soon start forming armies and navies before crossing it. Climate change and environmental degradation is driving them into a bloody war, which cannot but eventually engulf Europe entire. If the Mediterranean is still my sea, this refers only to times long gone. The Argonauts mark its beginning and the demise of Venice marks its end for me. As for today and the foreseeable future, I wash my hands of it. Mare meum, my ass.