A  Mexican police officer patrols the area where the bodies of Óscar Alberto Martínez Ramírez and his daughter Valeria were found on a bank of the Rio Grande in Matamoros,  Mexico. Photograph: Abraham Pineda-Jácome/EPA

The father and daughter lie face down in the muddy water along the banks of the Rio Grande, her tiny head tucked inside his T-shirt, an arm draped ove(...)

 A US  border protection agent drives along a fence  separating the cities of Nogales, Arizona and Nogales, Mexico – a frequent crossing point for people entering the US illegally. Photograph: Scott Olson/Getty Images

“If you build a 10ft wall on the Texas border, the 12ft ladder business in Mexico will boom.” This was the rather flippant opinion of Prof Mark P Jone(...)