High-Sec is misleadingly presented as safe (green/blue dots, except yellow for 0.5), implying it’s non-PVP. However, PVP is possible through War-Decs, Faction Warfare, trade hub camping, and ganking. Clearer rules would reduce complaints and clarify expectations.
CONCORD is one of several policing forces in High Security Space (0.5 to 1.0 security status), tasked with eliminating the ships of players that have illegally attacked other players. Such as attacks that result in the players receiving an active Criminal Timer in High Security Space.
While CONCORD forces do react quickly and with force, they do not have a mandate to protect attacked players and as such will not necessarily be able to prevent eventual losses if attackers can field sufficient firepower to destroy their targets before CONCORD can intervene. CONCORD should therefore be regarded as a force of retribution, not one of protection.
When it comes to PVE, Drifter NPCs in high-sec can one-shot Marauders, while Trig and Edencom NPCs may scram and pod you if your standings are low. In “high sec”.