The capture of Sveaborg was a major flip for the Russian campaign in Finland, as it removed the threat of a counterattack from the south and west. To Sweden it was a devastating blow as it made the resupply of the battered  Finnish army much more difficult.
The capture of Sveaborg represented a decisive shift in the Russian campaign in Finland, as it eliminated the threat of a counterattack from the south and west. To Sweden, it was a disastrous blow, making the reinforcement of the Finnish army much more difficult.