Was Dr. Smith Gay?

Millions of Baby Boomers know exactly who Dr. Smith was: the foil/ pain in the neck/ comic relief on the iconic sci-fi series Lost in Space (1965-68).

A nuclear family (Mom, Dad, teenage girl, preteen boy and girl), blasts off into space to colonize Alpha Centauri (how are they planning to increase the population?)

Enemy spy Dr. Smith (Jonathan Harris) tries to sabotage the ship, so it won't reach its destination -- instead it will be Lost in Space.  But he is accidentally  trapped aboard.

How on Earth is he going to be redeemed after that?

Easy -- the writers just forget about it, transforming him from evil to a pain in the neck, occasionally helpful ("I'll negotiate with the aliens"), occasionally devious ("I'll sell you the boy in exchange for passage home"), but usually just annoying ("I'm much too fragile to do any work!").   A vain, prissy, glutonous, lazy, self-centered uncontrolled id. 

Also the most interesting character amid the squeaky-clean Robinsons (quick -- name two character traits of the teenage daughter).

Dr. Smith spends a lot of time with preteen Will Robinson (Billy Mumy), whom he hugs, grabs theshoulder of, and calls "my boy."  Thus leading to speculation that he was gay.

Maybe, but he certainly wasn't in a gay-subtext relationship with Will.

An adult and a child can't have a gay subtext relationship, because the tropes of the parental relationship would overpower it.  Imagine man and boy walking off into the sunset together at the end of the adventure -- the man is going to adopt the boy, not marry him. 

 For a gay subtext, the two need to be in the same age category: both kids, adolescents, or adults.  Maybe an adult and a late adolescent, like the superhero and his teen sidekick. 

Well, did he have another sort of interest in Will?  Was he a pedophile?

Obviously not intentionally, but did some sort of pedophile subtext arise from the actors' interactions? 

Nope.  No way.  Dr. Smith never expresses any erotic or romantic interest in Will (or in anyone else except an occasional middle-aged alien lady, and then only when he is trying to get something, like dilithium crystals or whatever they use to propel the ship). 

He puts his hands on Will for protection, not affection.  He calls him "my boy" to signify pretentiousness, not possession.

By the way, Will expresses no romantic or erotic interest in anyone during the course of the series.  He's a little boy looking for a playmate, and Dr. Smith is the only member of the crew who isn't a girl (girls!  gross!) or busy with important scientific duties. Who else is he going to befriend?

You'll have to look elsewhere for a sexual theme on Lost in Space.  Let's talk about John Robinson (Guy Williams) and Don West (Mark Goddard).  Which was gay in real life?  I'm not telling.