Airport / airline security

Hi. A big thing that contributes to my fear of flying is concerns over security. Given our realities, can anyone in the airline industry please comment on the security of airlines? I get that we are screened when we go through security but what about checked bags? What about all of the folks who have access to the planes on the ground between flights? I assume it’s all pretty secure but can anyone please provide some reassurances?

I’m sorry if this seems stupid it irrational. It isn’t to me!

I re-read the rules and do not think this violated any of them. Thank you very much