Why do the tribunes disperse the crowd in Julius Caesar?

In Shakespeare's "Julius Caesar," the tribunes, Flavius and Marullus, disperse the crowd to protect the honor of Pompey, who has recently been defeated by Caesar. They criticize the citizens for celebrating Caesar's triumph and remind them of their previous loyalty to Pompey, suggesting that their fickleness is disgraceful. By dispersing the crowd, the tribunes aim to assert their authority and prevent the public from gathering in support of Caesar, who they see as a threat to the republic.