It's always good to have more going on in the background than the PCs are aware of. Having third party events happening around them, regardless of the PCs' action make the game world feel more realistic and alive.
Only you need to actually make the players aware of such background events at some point. You can start subtle, but you'll probably need to escalate at some point.
Transcript
GM: Your fighters squeeze through the closing blast doors and slide to a halt on the hangar deck.
[SFX]: Skkreee...
GM: Several combat droids start shooting.
[SFX]: Pow!
R2-D2: Awesome. It's a shame Jim and Sally aren't here for this.
[SFX]: Whooom!
[SFX]: Kzrkzk!
GM: The ship trembles from incoming fire.
[SFX]: Whooom!
[SFX]: Kzrkzk!
Obi-Wan: Hang on. Who's shooting at this ship?
GM: These ships on the map have been shooting at each other since you arrived.
[SFX]: Kzrkzk!
R2-D2: You didn't know that?
[SFX]: < squee boop fo-deep ping >
Obi-Wan: Yeah, thanks.
Obi-Wan: We're missing something important.
Obi-Wan: This is just like when Qui-Gon and I messed up our first encounter with the Trade Federation.
R2-D2: At least now you're aware that you're ignorant.
Anakin: It's a big step forward for us.