Okay, now Melania Trump is being attacked in a political ad and Donald Trump is fighting back.

Under normal circumstances, I unreservedly admire a man who stands up for his wife, but did Trump have to do it by attacking the wife of his GOP rival Ted Cruz?

In a season of new lows, this is a new lows.

The ad features an apparent photo of Melania Trump scantily, if at all, clad from a GQ magazine story.

The caption:

Meet Melania Trump, your next first lady. Or, you could support Ted Cruz.

Trump's response (via Twitter of course):

Lyin' Ted Cruz just used a picture of Melania from a G.Q. shoot in his ad. Be careful, Lyin' Ted, or I will spill the beans on your wife!

I am glad to say that the attack on Mrs. Trump did not come from the Cruz campaign but from an anti-Trump PAC over which the Cruz campaign has no control.  I would be sick if I though Cruz had stooped so low. Cruz also responded via Twitter:

Pic of your wife not from us. Donald, if you try to attack Heidi, you're more of a coward than I thought.

I thought Cruz's response was gentlemanly–but, oh, my gosh, how did we get here?

Political spouses of course are a complicated issue. A potential president's spouse can be a consideration. Marital relations can come into play when we select a president. This is far from the first campaign in which the spouse's private life is invoked.

Remember the Rockefellers?  When Happy Rockefeller lost custody of her children in a 1963 divorce, prompted by her desire to marry Nelson Rockefeller, the ensuing scandal (what an innocent age it was!) likely cost Rockefeller a spot on the 1964 GOP presidential ticket.

But I think we may be in uncharted waters when an uncouth and unconscionable ad of this sort appears about a presidential candidate's wife and the candidate responds by threatening to expose his rival's wife (Mrs. Cruz works for Goldman Sachs, and I imagine that will be Mr. Trump's line of attack, if it comes to that).

For the record: It was disgusting–and possibly counterproductive–to attack Melania Trump in this way. I hope this goes no further. But I am not counting on this.