A recurring theme I noticed in his films

Spielberg fan and kind of a long post. Did anyone notice that his films are about abductions in one form or another?

Sugarland Express
Close Encounters Of The Third Kind
The proposed sequel to E.T.
Poltergeist
Temple Of Doom
The Color Purple
Empire Of The Sun
Schindler's List
Hook
Amistad
The BFG
Bride Of Spies

Also his other films which you probably know also feature abduction and separation in some form without being the central theme or whatever.

The Terminal: Tom Hanks is caught in some international loophole that prevents him from leaving the airport thus kinda being captured by it.

Catch Me If You Can: The FBI tries to capture Frank Abignale.

War Of The Worlds: People are being rounded up in some scenes by the tripods.

War Horse: The horse Joey is being taken by the army.

Tintin/Jurassic Park/Indiana Jones franchises: Heroes get captured by villains.

Minority Report: Tom Cruise is being hunted down and eventually caught by the Police.

A.I.: Mechas are being hunted down, captured and destroyed.

E.T.: He and Elliot's family are caught by the government scientists and a thrilling chase ensues.

Munich: Eric Bana's character is swept up in the counter-terrorism events and kept from his family (though he willingly left).

The only movies I can think of that don't feature abductions of anykind or Saving Private Ryan, Lincoln, Duel, 1941 and Always.

His next movie: The Kidnapping Of Edgardo Mortaro, the title speaks for itself.

Also: Memoirs Of A Geisha, Super 8, Monster House.