Why doesn't military intervention in foreign conflicts work? Or does it?

When the United States military is unleashed, it is a juggernaut. Green kryptonite couldn't slow it down. Then our government got creative and decided that it was the military's job to be State Department employees and were to also be ambassadors, nation builders, civil engineers, media savvy spokesmen, social workers,........................
The last successful nation to be built post-war, by the military, was Japan....and that required nuclear weapons to get to the foundation that was necessary to rebuild upon. A nation that had been around for thousands of years, militarily hardened by the way of bushido.....reduced to rubble. When the will to fight was finally outmatched by their overwhelming misery, a new nation was reborn. Their very identity was forever changed.
We live in the world of public opinion, political correctness, and politicians who plan their every move based on their ability to hold onto power for as long as they can. The military works for the sitting POTUS and their own State Department. Rules of engagement are not designed to keep our warriors safe. Our troops are made to feel that their own nation will throw them under the bus whenever it is convenient. HRC single handedly destroyed the one thing that every warrior holds sacred; leave no one behind.
I have a difficult time trying to engage my brain housing group with our civilian leader's intentions. Apparently, so did so many of our key leaders. There have been so many quality military leaders relieved for one pathetic reason or another and usually it was for making a decision geared towards keeping their troops safe. I miss the simple days. The days when the military was unleashed like a plague upon our enemies.

That's a helluva good question and it seems it's one that many of us have been wondering about given the depth of comments in response. Personally, I think it doesn't work because it can't. (Now doesn't that sound stupid - but it's true). Ask any mechanic and they'll tell you. "I can fix anything if only I had a bigger hammer." It seems that the mechanic's in Washington have been playing by that rule for a long time.

How about using a different paradigm: Use the right tool for the job. If things need blowing up or people need killing, send in the military. If not, don't. And when you're done blowing up those things and killing those people, go home. If you need a nation built, let the people who live there build it. If they ask for help, help as little as possible so they will build their own government. Try reading the Declaration of Independence. It's a great guide to nation building.

One of our biggest problems is that we don't understand the cultures in the places we fight. I have seen this time and time again where we try to apply American ideals to people who aren't Americans. Another problem I see is that military leaders by and far don't study the history nearly enough. Right before I deployed to Afghanistan, none of my leaders had any clue that the Soviets fought a long brutal war there. And time and time again, we make the same mistakes. I think we need to really exercise more care before getting involved in places around the world. We should only involve ourselves in direct threats to us or our allies and let the chips fall where they may for the rest. It is not our job to depose dictators. Their governments exist with (at least on a nominal level) by the consent of the governed. It is not up to us to involve ourselves in the internal affairs of other nations. I am not suggesting we be totally isolationist, but we need to pick our wars carefully. Look at the last 15 years, what have we really accomplished other than depleting our resources and creating conditions that led to negative 2nd and 3rd order effects?