Why did Italian nationalists become disappointed with Pope Pius IX in 1848?

Italian nationalists became deeply disappointed with Pope Pius IX in 1848 primarily because he refused to support the war for Italian independence against Austria.12

Although Pius IX initially inspired nationalists with his liberal reforms—such as granting amnesty to political prisoners, easing press censorship, and admitting the laity to civil administration—his position became untenable as the revolutionary movement gained momentum. When war broke out between the Italian states and Austria, the Pope faced a fundamental conflict between his role as a national leader and his position as the head of the universal Roman Catholic Church.31

Ultimately, Pius IX refused to authorize the Papal States to participate in a war against a major Catholic power, Austria. This decision alienated the nationalists, who viewed his refusal as a betrayal of the Risorgimento. The resulting tension led to a revolution in Rome in November 1848, which forced the Pope to flee the city and eventually led to the declaration of the Roman Republic in 1849.12