The same technologies which are going to be needed to divert the next impactor away from the Earth, and thus save countless 10's of millions of lives, are exactly the same technologies needed to divert an impactor into Mars and thus release its volatiles.

Further, we have those technologies, but we simply are not applying them to the most essential problem, the preservation of the lives of 10's to 100's of millions of people here on Earth. Think of 2 to 3 World Wars 2's in an instant, and further, based on the historical record, we can expect one of these about once in 1,000 years.

The next problem is that once you have released the volatiles, Mars still would lack a magnetosphere, and thus would be bathed in deadly levels of solar radiation.

The other problem is that life may exist on Mars, may thrive in the newly created environment, and thus may make Mars inimicable to human settlement.

While this is all entertaining to speculate on, without data that speculation is little more than entertainment. On the other hand, while some do their best to deny it, we know that we face a very real threat from Earth impactors.

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