Yes, the Western world has persevered in its fight against ISIS, and as a result, ISIS is losing its grip in Syria. It was only a matter of time, since most of the world frowns upon ISIS's use of terrorism and brutal tactics. The airstrikes on ISIS strongholds have proven successful in helping enemies re-capture ISIS strongholds. When countries unite to combat terrorism, group like ISIS cannot thrive. However, there are many radical groups in existence around the world. Members if ISIS will join these groups if ISIS eventually gets dissolved. Nations such as the US should not let their guard down. Keeping nations safe and secure is an on-going process.
The answer is you can't because Isis isn't just a country it's a random group of people from all corners of the world. If somthing is united by religious groups then it's a lot harder to tackle. And that's why we can't win against Isis and why religion in general is a terrible idea in 1 post.
Millions of murders later and complete disregard for human life, and it's safe to say that the West is not winning the war against ISIS. Time and time again, ISIS is able to penetrate into free societies and kill innocent people. It's hard to fight an enemy that has no problem with suicide. ISIS is a threat all over the world, and the West is doing what it can, but it hasn't made a dent in ISIS' power.
The west is not winning against ISIS because they are not currently willing to do what it takes to defeat their enemies. Winning a war means destroying the enemy's capability to make war. There is no sign that the west has made any headway at all in that regard. In fact the forces hostile to the west seem to be gaining in strength. Weakening the despotic governments ruling in that part of the world has created a power vacuum, where groups like ISIS can flourish. Until the power vacuum in the region is filled by a stable government, ISIS and groups like them will continue to flourish no matter how many times they are bombed.
No, I do not think the Western world is winning the war against ISIS because the group is still carrying out terrorist attacks all over the world and its forces are still growing. The United States and other major countries in the world need to create a coalition that takes out the leaders of ISIS and permanently cripples the terrorist organization.