HARF: We’re killing a lot of them and we’re going to keep killing more of them. So are the Egyptians, so are the Jordanians. They’re in this fight with us. But we cannot win this war by killing them. We cannot kill our way out of this war. We need in the medium to longer term to go after the root causes that leads people to join these groups, whether it’s lack of opportunity for jobs, whether —Generally speaking, you don't end or win a war until one or both sides exhaust themselves, and no longer have the will to continue. In total war, such as in World War 2, the prospects are ghastly as all sides have a stubborn determination to continue, and the means to do so. Hence, it takes the near total destruction of the enemy to win ... the destruction of his armed forces, his industrial capability, and the killing of so many of his soldiers and civilians that once defeated, he remains defeated.
In asymmetrical warfare, such as the Iraq War, the same principal applies to some degree, as was demonstrated by The Surge. The battle for "hearts and minds" turned out to be a fool's errand as long as enough of the enemy was willing to keep fighting. All the school supplies and hospital constructions in the world couldn't outweigh the constant instability caused by the Iraqi Sunni and Shia insurgencies.
The British Forces in Basra, in fact, were utterly defeated simply because their leadership failed to recognize that killing the enemy in large numbers was the only way to win. After the British had all but bugged out, an Iraqi and USA force came to assist and in short order had killed its way to victory. The Basra insurgency never recovered; neither did the hapless British who skulked off back to the UK as losers. One can only feel great sympathy for the UK soldiers who had known all along what needed to be done, and instead were prisoner to the Progs of Whitehall.
What changed things was the realization that the insurgency had to be crushed; while the humanitarian efforts continued. So it was, that once the Anbar tribes were slaughtered in large enough numbers (thanks to warriors like Chris Kyle) they came to the table and turned against the most vicious of their allies ... the fundamentalist pre-ISIS terror groups. The tide then turned, and by the time Obama bugged out of Iraq, the tribes were allies of America, not enemies. By demonstrating the ability to be ruthless in war, yet compassionate in victory, America convinced the tribes that dying in droves just wasn't worth it. Essentially, America killed its way to victory.
One has to ask , in the case of ISIS (and all Islamic fundamentalist organizations), what are they willing to give up in order to stop the bloodshed. Unfortunately the answer comes loud and clear with each beheading ... nothing.
Therefore, like it or not, the Civilized World is already locked in a total war with fundamental Islam. It's just going to take the vast majority of Progs, many of whom run governments, to face the ugly truth before the war is fully engaged. Until then, things will only get worse.
As to wars like the Ukraine conflict, there may be hope of ending these, without total victory on one side.
Wars can be ended without either side losing the will to win simply because most wars are not "Total Wars." In this case, there is usually not a victor. In some cases, as in the Cold War, there was an initial victor ... but one could argue that all that happened in the end was that the West was seeded with millions of Marxists turned Progs who are to this day causing mischief (note the quote at the top of this post)
“War, it seems to me, after a lifetime of reading about the subject, mingling with men of war, visiting the sites of war and observing its effects, may well be ceasing to commend itself to human beings as a desirable, or productive, let alone rational, means of reconciling their discontents. This is not mere idealism. Mankind does have the capacity, over time, to correlate the costs and benefits of large and universal undertakings. Throughout much of the time for which we have a record of human behavior, mankind can clearly be seen to have judged that war’s benefits outweighed its costs, or appeared to do so when a putative balance was struck. Now the computation works in the opposite direction. Costs clearly exceed benefits.”
Unfortunately, it takes two sides to be willing to weigh the costs and to come to a mutual understanding free of armed conflict. In the case of Islamic Fundamentalism though, the gap between Western Values and the Barbaric Creed of Muhammad is far too wide.