Because they aren't internal - they are impacted by it with broad reach. There have been many stupid attempts to target Google in the past from vested interest

Because they aren't internal - they are impacted by it with broad reach. There have been many stupid attempts to target Google in the past from vested interests (snippet tax, link tax) - but this one isn't very objectionable. The main legitimacy to the complaint is that even though nation neutral it is defacto targetted by industry concentration because of the lack of international Spanish internet companies. A flimsier one but there. The second is the populist rhetoric to sell it caused offense by targetting their companies. Plus countries in international relations are best anthropoisized as a bunch of hypocritical petty bastards. A flatter 3% corporate tax rate wouldn't have those grounds but would piss off the local corporate interests and possibly ideologe powers abroad still.