1. It has a defined and measurable aim (end an occupation, remove x from power, stop a genocide, etc);
2. It has broad agreement on that aim;
3. It ends within a reasonable timeframe, to whit a decade or two.

Of course, these are just my own signs, but I think that they make a certain amount of sense. Now, let’s have a look at the War on Drugs against that, shall we?

1. The aim is to try and stop the production, import and use of illegal drugs. Except that not all states agree on what is an illegal drug or how seriously they take the issue.
2. Vast swathes of most countries use illegal drugs to some extent, and many leaders of countries have admitted to using said drugs during the time of the War on Drugs.
3. It’s been going for decades and use is only ever going up.

Time to cut losses and stop fighting silly fights that criminalise people for enjoying themselves in ways that only cause harm because a part of it has been made illegal, do you think?