Oh, you actually believe them when they said we wouldn't need defense? Lol ok buddy.

No defense needed because everyone died after a series of unfortunate disasters struck in rapid succession and there was no hope of self-rescue or Earth-based rescue. Mars is an exercise in unhinged hubris that will end in mass death at least if it is attempted in the foreseeable future. The logistics are far beyond anything we have ever attempted nevermind succeeded at, and Martian nature makes Mother nature look like the kind gentle mothering figure she actually is in comparison. If you think she can be harsh with what she's going to do to us over climate change, just wait until we see how cruelly the rest of the universe is going to treat us.