OK.... this is getting back on-topic....
It has been established that "civil unions" can grant all the "rights, benefits, and privileges" (as well as responsibilities and obligations) of marriage. The "short comings" of civil union laws in the US can be corrected.
I can find no record of, and no example has been given of .... any society in the history of mankind that has recognized G*y marriage. This applies whether the society is a theocracy or secular or atheistic. It applies if the dominant religious belief is Christian, or Muslim, or Jewish, or Buddhist, or Shinto or atheism. Even those societies that has "open" marriages (such as many Polynesians) have not recognized G*y marriage. For that reason, while in the USA, Christians are the most vocal opponents to G*y marriage, this is not a religious issue.
I had earlier provided a definition of "marriage" from a 1913 dictionary showing the institution is between a man and a woman. Now, I have access to my 1958 dictionary and it says this:
"1) State of being married, or being united to a person or persons of the opposite s@x as husband or wife .... the institution whereby men and women are joined in a special kind of social and legal dependence ...." (emphasis Pi's)
(Source: Webster's New International Dictionary, 1958 .... this is one of those 6 inch thick dictionaries that weighs more than my bowling ball...)
Hopefully, that establishes that the heterosexual nature of marriage has been explicitly incorporated into the definition until recent, politically correct times.
I fully support that G*y couples can, and should, be given all the legal rights, privileges (and obligations) of marriage. It is not necessary that we call such unions "marriage" in order to assure those rights are granted. I find no legitimate reason to re-define a term that has been in use for all of human history to satisfy a few politically correct activists.
G*y civil unions with all the rights of marriage.... absolutely yes. G*y "marriage" .... absolutely no.
Would you be willing to give up all talk of "marriage" in legal discourse and make all unions G*y or straight "civil unions"?
The idea that civil unions can, as a matter of practical reality, be granted all the stuff marriage provides is a fantasy, at least here in USA. Not because of any linguistic strain a bill may have to endure, but solely out of political reality. It would take years of work at the state and federal level; for starters we need the federal government to recognize civil unions which they never have, and about 80% of the states don't have any civil unions last I checked - each state has their own laws on marriage as well which must then be mirrored in civil unions through legislative action (each state must do this separately). On top of that the Supreme Court does not have any authority to make laws, so they cannot create civil union legislation or dictate what is in that legislation beyond saying if it is constitutional.
The reality is that the only way to ensure equal treatment without indulging in political fantasy that would take years to accomplish even if successful, is to simply state that you cannot deny legal marriage on the basis of gender as it violates equal treatment set forth in the 14th amendment as the SCOTUS ruling did.
As for redefining the term marriage I don't see it as a big deal. The definition of words are not set it stone. Words can and do change definitions, never mind words can have more than one definition to boot. In addition various types of marriages have existed throughout history, and people marry for all kinds of reasons. More importantly why should we let civilizations that have long since been gone dictate how we conduct our lives in the here and now? Shouldn't it be enough that we recognize how marriage is practiced and used today, and make policies that make sense in the present? After all, as I'm sure you're aware, just because something is old or traditional does not in any way make it correct or moral.