In Cormac McCarthy's novel "The Crossing," the quote "There ain't no law in Mexico. It's just a pack of rogues" reflects the lawlessness and chaotic nature of the setting. This statement suggests that the absence of formal legal structures leads to a society where moral ambiguity prevails, and individuals behave according to their own codes of conduct. The atmosphere is one of danger and unpredictability, where trust is scarce and survival depends on navigating through treachery.

The quote encapsulates the broader themes of the novel, which explores the complexities of human existence against harsh landscapes. It highlights how characters must confront both external turmoil and internal struggles as they traverse the wild terrains of Mexico. The idea of rogues also evokes notions of freedom and rebellion, suggesting that in a lawless environment, people forge their own identities amidst the chaos, often leading to profound consequences for their journeys.