But the US is supporting Saudi Arabia in Yemen right now. It's just as much of an ongoing situation so there isn't even that excuse of "that was before and now is now".
And I don't support it. But that has nothing to do with the current situation in Russia or the Ukraine. Focus please, one problem at a time.
Pointing out double standards is not futile or pointless. It exposes the true intentions and interests of those who have them. In this case, for example, the double standards of Western governments and elites show that they do not really care about the suffering of people, rather they act based on their (geopolitical? economical? general?) interests. So, in some occasions they themselves help destroy countries and have no problem with it (Not caring about people's suffering: confirmed), then an opponent creates suffering and they react (is it because of the suffering? No, they proved they do not care.). It is relevant to this, past and future situations, because it helps (those who wish to understand things, at least) shake off pretenses of the various players and see the real motives clearer. Repeat for any other section where double standards exist to get a clearer picture.