War of the World Goliath, an animated movie slated by Heavy Metal magazine as ongoing series has had a troubled birth. Now re-imagined as a complete movie this Steampunk/Dieselpunk story finally saw a limited release in 2013. Which means we might start seeing this out on DVD soon. The concept does look very interesting a world-wide defense force raised on the tech from the first Martian invasion, although like you I do remember how poor Heavy Metal animations usually end up being. The trailer is below and if you want to learn more click here.
[UPDATE 08/04/2016] I finally found this movie on Netflix, purely by accident, and sat down and watched it. I feels like we had half a promising animated movie and the rest was slammed together using clips, and stock footage – most likely when the money was running out. You can actually see the bits that were meant to be episodic and the entire movie is clumsily cut together to fit a 90 minute running time. This actually did have potential to be a really good story, but like most Heavy Metal productions it did not live up to the potential.