At the very least, its currently necisary and I'd argue its more than that but clearly currently necisary is the laziest argument you can make for government.
Well, you gotta start somewhere! ;)
Seriously though I it's the laziest argument you could make. I think it's actually the most salient one. Anarchy is impossible, and while you state "currently" the reality is the things that make it impossible aren't changing any time soon.
I've actually realized recently that anarchism is an attempt to fight the symptom rather than the actual problem. The problem isn't government, it's people who desire power and want to or are willing to harm others for their own gain. Get rid of those, and government becomes irrelevant, as no one in government would pass tyrannical laws anyway.