[HerenIstarion]

if we consider Eldarion as half-elven,whole system of the world is crushing down. The meaning of the Aragorn-Arwen union is reunion of sundered blood of those, whose ancestors were three kindreds - Maiar, Elves and Men. By achieving this, with the start of the Age of Men, the line with such blood reunited in it's veins obtains mystical right to be theKings of this renewed earth, but being mortal, of course - cause the time of elder race is gone for ever.