The pure violent means, that is, war, and the reason Freud did not account for Austria having already formed an army and existing in the Pope Country, is because the Pope Country is transparently one-sided to the Kingdom of Italy.
Contrary to what Pius IX guessed, the intelligence system of the Austro-Hungarian Empire in the Italian region cannot be said not to exist, but is almost nonexistent.
Yet the Kingdom of Italy can easily infiltrate the Pope Country, learn about its specifics, as the Pope Country is a theocratic regime. Since it is a religious state, naturally it cannot block believers from visiting, and the populace of the Pope Country are also Italians, deep within the heart of Italy, making it impossible to block the exchange of people and trade.
