That's it. Right there.
It's been that way for 3,000 years. The creatures there have not advanced much beyond that. They are uneducated, cruel savages - barely human. More neanderthal than sapien. It's like tenth century goat herds got ahold of modern weapons. It's like giving a hormone soaked teenage girl a revolver.
Civilization has been trying to deal with these assholes for thousands of years. Throughout history it has been demonstrated that nothing works with these brain-dead zombies. The only thing that works every time - is death.
So, the only choice we have is ... fight them there, or fight them here. But, they're not going to stop.