The progress from first man made flight to landing on the moon was largely driven by world encompassing wars. A huge amount of research and development went in

The progress from first man made flight to landing on the moon was largely driven by world encompassing wars. A huge amount of research and development went into aeroplane design as people quickly realised they could be used very effectively for reconnaissance, strafing infantry, bombing and resupply. This led to the development of air to air combat which led to faster planes and eventually jet engines. The German development of the V2 rockets for bombing London from a great distance led to a lot of work on rocketry which was then able to built on for the space race. The space race was two super powers pouring enormous resources into research and development to ensure there would be no military gap from lack of capability in near earth orbit. From a military perspective, colonising Mars is unlikely to have any major military benefit on Earth. I'd guess there are many other hot topics for the military to focus on (autonomous/semi-autonomous warfare, cyber warfare, biological warfare etc). Colonisation of Mars is (currently) more likely to be pursued by commercial or non-military scientific purposes. Perhaps some of the commercial entities now rival small countries in terms of economic might. I doubt though that a commercial entity (Space-X) will be able to get very large groups of people to unite (and sacrifice other interests) in pursuit of a common goal in the same way that they do during times of conflict.