What part of this is hard to understand...
Either the fault is with Islam who can not treat individuals and empower them or the fault is with you who can not understand it.
It is NOT the job of the Government to intervene in who marries whom. The people over the legal age limit are individuals with their own minds and are empowered citizens. They are not slaves that they are to be told who to marry and who not to, they can make their own choice about whom to marry.
This is a basic idea of liberty and freedom. Is it hard for you to understand?