Final answer:
The cartoon seems to suggest that Mexico faces significant challenges in achieving progress as represented by the endless running on a treadmill facing a setting sun.
Step-by-step explanation:
The cartoonist's message in the described political cartoon, depicting a Mexican man running on a treadmill facing a setting sun labeled progress, is likely a commentary on the challenges Mexico faces in achieving progress. The imagery suggests that despite the efforts exerted by the Mexican man (symbolizing Mexico), the goal of progress remains elusive and potentially unattainable. Such cartoons often reflect on socio-economic and political obstacles that hinder the advancement of a nation. Without the direct image to analyze, it is difficult to determine the exact sentiment being expressed, but generally, this imagery portrays a sense of futility or struggles against systemic issues.