THAILAND AND Cambodia have mostly kept heavy weapons out of their long-simmering border disputes. So the sudden violence on the morning of July 24th came as a shock. Cambodian artillery shelled a Thai military base;

Of course, trouble at the 508-mile (817 km) shared border is nothing new. For over a century, Thailand and Cambodia have contested sovereignty at various undemarcated points in the thick jungle punctuated with culturally-significant temples albeit with scant strategic or economic value.