Invading other countries to take their resources and kill civilians is not defence.
With your logic, Russia is also acting in a defensive manner.
With your logic, Russia is also acting in a defensive manner.
Russia absolutely has reason to not want Ukraine to join NATO. I'm not condoning the invasion, but I say it absolutely makes sense for Russia to carry it out. Not a reason to commit war crimes, or to cause any more suffering than necessary, but from a national security perspective it makes sense to want to disrupt the process of Ukraine joining NATO.
A former Russian foreign minister has labeled NATO "free-of-charge security" for Russia, because NATO membership requirements turn a country into a stable and predictable place. The best neighbors Russia has are in NATO, and much of that stability is directly attributable to their membership.