The dates are important if the kids are to draw their own understanding of history. They can be told that X caused Y and just accept that the X came before Y, or they can learn the dates well enough to examine the situation themselves.

For instance: How long was WWII? How long was Vietnam? When exactly did WWII start, before or after US involvement? Knowing those sorts of dates allows students to put today's wars into context. Has the US been in Iraq longer than WWII? Longer than Vietnam? They can memorize the dates and answer those questions themselves. That makes them informed citizens, and some of them eventual informed soldiers, better able to participate in very relevant current events.

You know what would be useful? Take all those events and ask the children to put them in a time-line. Let them search any book they need in the process.

You know what is completely useless? Telling the date each happened on their respective classes, and that this knowledge will be tested.

I disagree that it is completely useless. You're basically arguing that time is only useful as a relative measure, not an absolute one. While that is true in some sense (the ordering of events and the space between them is what matters), because history is so vast and interconnected and a total ordering is desirable, it just makes more practical sense to learn the absolute date of an event, not just the "relative" date

That would have been nice, if students actually internalized the dates they've been taught.

Memorizing dates is as dull as it can be, without having motivation from knowing the context. Dull things get crammed for tests and then forgotten, with near zero retention when those people grow up and actually want to use the context.

Even if dates were more important than causes, they stick less, reducing the utility of teaching them.

In my history classes we were never quized directly on things as dates. However, you were expected to be able to use those in context. Example of a question: "Some historians consider the Cold War to be an ideological conflict that already started in 1917, argue why:"