He was worth millions. He could have gotten a decent sized RC plane (to house said duffel bag sized bomb) and had it fly to the concert autonomously. He wouldn't have even needed to be in the area for it to launch and hit. Off the shelf components would have worked fine.

Source: I fly autonomous drones for fun as well as work.

When it comes down to it, life is filled with danger. If you outlaw guns, people will kill with other means. In countries where guns aren't legal, there are less gun deaths but a lot more stabbings. Before you claim that lack of guns means much less deaths in mass killings such as this, consider that someone could have fucked up the entire area with carfentanil, which can be aerosolized. It only takes a tiny amount to kill you. Want to tell me how difficult it is to obtain? We're getting overdoses out the ass with it already in the country. Bombings are also much better than guns for mass killing, and have been used in Arabic countries for decades.

Anyway, my point isn't that we shouldn't try to combat mass murders. We should, but we should focus on the root cause, not the tool used.