First line of the article:
'I am sure as hell not going to tell a single person to go there and die in a foreign country. I learned that lesson with Iraq and I am never going to go through that again.' @greggutfeld
I think that it's obvious he means that, in previous conflicts, he may have (directly or indirectly) encouraged patriots (for the cause of freedom) to go and fight, and that he now regrets having done that.
Regards,
That is how I read his quote.
Gutfield provides zero context for this statement. So no one other than Gutfield knows what he meant by this tweet other than that he might have had some personal epiphany related to war. The statement could easily be interpreted to mean that he told (advised ?) an individual he knows (or knew) to go to war overseas and regrets having done so. Or it could just be one of those “hey, look at me” moments media personalities love to indulge in from time to time.