War with France could leave Mussolini confident enough to attempt to supplant the monarchy. His dictatorship still operated alongside senators and parliamentarians willing to challenge him. The armed forces also contained officers tied to the nobility and royal family, even among people sympathetic to his supporters. A confrontation with those established powers could remove him from office and change the European balance again.
Notable Point · 1:33:24-1:34:12
Why Mussolini's monarchy dispute could change the scenario
A confident Mussolini might challenge the monarchy after war with France, only to find that royal and noble loyalties still limit his control.