Isn't this the same basic argument that goes "anybody can get married, so long as you marry somebody of the opposite sex"?
No, because no specific individual is given a right to polygamy over another.
The argument from your quote clearly discriminated against those who wanted to marry the same gender. But in the case of polygamy, no one can be in a marriage of more than two - be they straight or gay, man or woman. It's precicesly because polygamy is outlawed for everyone that it doesn't discriminate against anyone.
Because polygamy is illegal for all, polygamy relationships do not exist? because gay marriage was illegal (in some states), homosexual relationships did not exist? Because interracial marriage was illegal, there were not case of black/white relationships?
A marriage is a contract. The dude has to marry at least one woman. The other wife is left with less rights than the real wife. Both women are happy, have children, live under the same roof.
Why would anyone deny equal justice to both women, letting the real wife have all the rights once the husband dies? Because it is justice? Because it is the law?
Everyone in this situation is an adult. Gay adults should be happy, but not polygamists? Are you saying polygamists are less 'adult' than gays and should not be able to know and define what love is?
By the way, "government cannot define love" is pretty much the justice's conclusion for ssm. But you are saying in the case of polygamists government SHOULD definitely define what love is because love is defined the same for everyone else... Is it?
Give it time. Now that the supreme justices gave themselves the power to write new laws I don't see how people like you with infinite amount of IPAs can stop the legalization of polygamy in the future.