Because you see Jews everywhere wearing armbands too...Women being forced to wear the hijab is oppression. Women choosing to wear it isn't
Oh wait, no you don't. And yet some people here think the hijab is merely about modesty? So all those Iranians trying to cast it off are whores? Yes I used that word. That's the argument used as to why women should WEAR it. And it's horrific.
1. Because I'm not in the USA.And while there is definitely a valid point in that they are only choosing to wear it because of sexism inherent in Islam, why don't you get up in arms about the ultra-Christians here (well, in the US at least) that essentially force their women to dress modestly as well?
2. Because those "ultra-Christians" as you call them also aren't known for killing those who don't conform. Banish from their societies yes, but you don't really hear about them killing or beating those who don't conform. With the hijab, here's some cases in Canada alone where this happens. Asqa Parvez, Quebec Assault, and let's not forget the hockey-stick assault refugee.
3. Most of the groups with strict modest dress rules in Canada and the USA are isolationist groups, not proselytizing sects. Mennonites, Amish, etc. Islamists are pretty much exactly the opposite. Thus saying "look out for the spread of the Amish philosophy against women!" is kind of useless. But look out for this anti-woman philosophy spreading like crazy (for some reason)? Ya, it's different.
4. Related to 1, I speak out about it becoming more prevalent in Canada, primarily. It was just a good opportunity to remind everybody about it and how it relates to the situation in Iran from those living under it.
So no, it's not as big a deal as (usually isolationist) Christian groups doing it. Is it good? No, but it's not the same either.