Martian gravity may be easier than weightlessness, but nobody knows whether 0.38g is enough for lifelong human health, pregnancy, child development, bone strength, muscle maintenance, and psychology.
Mars radiation is not an instant death sentence, but it is a chronic settlement hazard that requires shielding, storm shelters, dose limits, medical monitoring, and underground or regolith-covered architecture.
A Mars emergency would test isolation doors, life support backups, food reserves, microgrids, medical systems, communication delay protocols, and the city’s ability to keep breathing while it repairs itself.