That's a really inaccurate and offensive way to simplify the issue, much like the out-of-hand comparison to female genital mutilation.
Your argument is consent. That is also pretty much the only good one, along with a potential loss of perhaps some loss of barely quantifiable sensitivity in the tip of the penis specifically and nowhere else, and a possibility of irritation later in life without the protective foreskin there. You're right, it is plainly exactly like the cutting of the rose (the entire forcible removal of the clitoris) and other similar procedures that incise nearly the entire vulva, painfully exposing the first portion of the interior of the vaginal canal, a mucus membrane never meant to touch open air, with the cut flesh crudely stitched together in such a way as to keep the channel forced open permanently to make spontaneous, nonconsensual sex easier for the male to perform.
Then you have infibulation. The entirety of the external genitalia are removed with the outside edge of the labia majora pulled together so they heal except for a "matchstick sized" hole for sex, bleeding and urination:
Quote:
Bleeding is profuse, but is usually controlled by the application of various poultices, the threading of the edges of the skin with thorns, or clasping them between the edges of a split cane. A piece of twig is inserted between the edges of the skin to ensure a patent foramen for urinary and menstrual flow. The lower limbs are then bound together for 2–6 weeks to promote haemostatis and encourage union of the two sides...
Healing takes place by primary intention, and, as a result, the introitus is obliterated by a drum of skin extending across the orifice except for a small hole. Circumstances at the time may vary; the girl may struggle ferociously, in which case the incisions may become uncontrolled and haphazard. The girl may be pinned down so firmly that bones may fracture.
When men need to penetrate their wives, they simply force their penis through the "matchstick sized" hole progressively over the course of days as a way to show they are man enough to force it. However, it's common for them to simply cut the flesh covering the skin open for sex, then force it to heal again once they're done, so their vaginal skin is being cut open each time. In some cases it's recorded that the scar tissue from cutting them open for sex repeatedly becomes so strong the men have to use high grade surgical scissors to achieve penetration.
There's also the ritual burning with fire and chemicals held against or inserted into the vagina for the purpose of removing sensitivity in the nerves through severe, irreversible damage known to kill the woman, forcing caustic chemicals into the vagina to keep it "tight," and using a knife to cut the anterior wall of the vagina so it's bigger when and if it heals.