I love that you can correctly translate this as "The Force is not important here". Words cognate to siła are used in most slavic languages for "The Force" from Star Wars (see Пробуждение силы or "Probuzhdenie Sily" for "The Force Awakens" in Russian), but in Polish it is actually translated as "Moc". Just a fun little tangent.
In terms of phisics Force is Siła, and Power is Moc, but those two are often mixed up, especially when describing things figuratively. And I guess if Power is often translated to Siła, translator went less travelled route and translated Force to Moc.
Does siła refer to physical strength only or also emotional strength or strength of character etc?
I'd say physical, unless you specify it: "siła charakteru", "siła emocjonalna" (? not sure if the second one is in use)
Ok, I'm not an expert, but I would put tutaj either at the beginning or at the end. If it were 'tu' I would put it second after siła or before ważna. But seeing 'tutaj' before ważna seems a bit unusual to me. Does someone agree?