Learn Portuguese (Portugal): O golpe foi perfeito? Sem dúvida que o foi. - Was the strike perfect? Without a doubt, it was.

It is the neuter predicative clitic, and it replaces the adjective perfeito from the previous sentence. While in English we can just say "it was" and leave the adjective implied, Portuguese requires this invariable o to stand in for a predicate adjective or noun.

Why does the pronoun come before the verb here (o foi) instead of after (foi-o)?

The conjunction que is a strong "magnet" word (a proclisis trigger). Whenever que precedes a verb, it pulls the pronoun to the front, forcing it to be o foi rather than the default European Portuguese placement of foi-o.

Why is there a que in Sem dúvida que? We don't usually say "Without a doubt that..." in English.

In Portuguese, it is very common to use que after adverbial phrases of certainty (like sem dúvida, claro, or com certeza) when they introduce a conjugated verb. It functions as an emphatic particle connecting the phrase to the clause, loosely meaning "Without a doubt, the fact is that..."

Could golpe mean something other than a physical "strike" in this context?