My impression from talking to veterans of various ages from various conflicts is that they felt very much as you say it--they didn't feel any glory was in it, they went because they were convinced it was a necessity.
The disgrace here in the US is that so many of our young people were convinced of this necessity by a shamelessly irresponsible lie. Those kids' efforts to improve things and make a difference have been squandered with poor planning and worse execution past unnecessary deaths into outright evil. They wanted to be building schools and repairing wells and making sure both our own and another country's people could sleep safe at night. They aren't going to buy into anybody's rhetoric any time soon after their experiences there. The level of anger over here has been incredible, but apparently that's what it finally took to get through to people clinging to illusions.
I don't think veterans have a lot of patience with illusions.