My comment is about the crux of the matter.
Wars are bloody and costly in the one thing that you can't readily replace: human lives (you can rebuild houses, tanks, etc, but you can't resurrect the dead). A life is the one thing we cannot rebuild.
I don't think you are thinking about this hard enough.
They are sending your coworkers, neighbors, friends, children, siblings, spouses to danger and a significant number will get slaughtered, often in an horrible violent way (and a fair number of them will live, but get maimed pretty badly). Think of it as if they were sending people related to you in the above manner away to danger (heck, think of it as if they are sending you away to danger).
You better think long and hard about what you are trying to achieve, because this ain't no video game (its the real thing... people dying out there don't get a 're-load last savegame' button).
You need to go into a war with a clear objective, the objective must be important enough for a bucketload of people to give up their life for often in a pretty horrible way (because they will) and you need to determine how much you are willing to sacrifice for your objective (1k soldiers? 10k soldiers? 10% of the country's population?).
From there, you can make an estimate of the expected losses and determine if the war is worth it.
This was not done properly with the Iraq war and I think the cost of the war far outweighed the benefits that were reaped from it (so how can you really think about this in terms of winning?).
Its should never be about something as stupid as pride or refusing to 'lose' or showing people out there who is 'tough'.