What are the views on the legalization of gay marriage?

Gay marriage would undermine the fidelity of marriage

Question: What are the views on the legalization of gay marriage?
Position‹3 of 4›: Gay marriage should be illegal
Argument1 of 3›: Gay marriage would undermine the fidelity of marriage

Gay people are more prone to extra-marital affairs. Allowing them legal marriage rights would undermine the fidelity of marriage.

The argument

In a recent survey, more than 79% of heterosexual men and women and lesbians in civil unions said they strongly valued sexual fidelity. Just 50% of gay men said the same. This illustrates the disregard for sexual fidelity among the gay community. Sexual fidelity is a widely accepted and celebrated norm of marriage. To allow homosexual couples to marry or enter a legally recognised union would be at best a disregard to marital fidelity, and at worst an endorsement of infidelity.

Context

Gay people are more likely to explore extramarital affairs than heterosexual couples. Therefore, allowing them to marry would undermine the fidelity of marriage.

Premises

[P1]Sexual fidelity is a widely accepted and celebrated norm of marriage. [P2] Survey data shows that gay men value sexual fidelity at far lower rates (around 50%) than heterosexuals and lesbians (over 79%). [P3] Legally recognizing gay marriage would therefore institutionalize a disregard for, or endorsement of, marital infidelity. [C] Therefore, gay marriage should remain illegal in order to preserve the fidelity norm of marriage.

Counter-arguments

We allow serial cheaters to get a marriage license and marry a new partner. The government’s role is not to uphold the fidelity of marriage. Additionally, this argument does not rule out allowing gay people to enter civil partnerships.

Rejecting the premises

[Rejecting P3] The government's role is not to protect the fidelity of marriage. [Rejecting P4] Gay people can still enter civil unions or partnerships.