US border walls are controversial - but are they effective?

2023-10-07 00:18

Barriers have been a feature of every recent US presidential administration's border policies.

At first glance, Starr County in Texas is a quiet place.

Its gently rolling hills are blanketed with low-growing mesquite and shrubs intersected by small gullies and streams, and many of its small, sleepy towns seem plucked from old Westerns.

But the US border with Mexico is never far off...