Mexican Military Incursion into US territory

[whell]

It happens once, its a major FUBAR by the Mexican military. It happens twice, and you have to start wondering. If we're not rigorously protecting our borders, why should the Mexican military respect them?

http://www.krgv.com/news/local/story...ytja1xnKg.cspx

I wonder how an "accidental" incursion by the US military into another country's territory would be treated by that government's leadership, much less our own press?