We do if we want to treat people fairly.WE don't have to do doodley!
It does if it doesn't want to be seen as endorsing discrimination on the basis of sex.The Supreme Court doesn't have to do anything either
The issue isn't "sexual preference" (by that, I assume you mean sexual orientation). The issue is discrimination on the basis of sex. Even without an amendment, the USSC can rule that such discrimination violates due process, as well as the good faith and credit clause.There's no amendment regarding sexual preference.
Let us know when Fido is capable of giving informed consent to a marriage contract.If some nutjob decided that they cannot be happy unless they can engage in marital bliss with Fido
The majority of Americans already support the legal recognition of same-sex marriage.You don't have to have consensus.
But I guess that is upsetting to homophobes.