OUR SOUTHERN SIEVE

Sovereignty: Suppose someone told you a foreign army had violated our
border not once, not twice, not dozens, but hundreds of times over
the past 10 years. Serious problem, right?

Of course. Yet that's exactly what Mexican soldiers have done,
according to the Homeland Security Department. In documents obtained
by several news outlets, the department details 216 crossings of the
U.S.-Mexico border since 1996. Roughly 35% of them have taken place
in California, 29% in Arizona and 36% in Texas.

U.S. border agents complain of being shot at by uniformed Mexican
troops, with the violence growing over the past two years. Things
have gotten so bad that the Border Patrol has told agents in Arizona
to be on the lookout for Mexican soldiers "trained to escape, evade
and counterambush" if discovered.

For its part, Mexico claims drug smugglers are dressing as soldiers
to gain access to the border, and that its own army has "strict"
orders not to go within a mile of the border.

American border agents don't buy it.

"Intrusions by the Mexican military to protect drug loads happen all
the time and represent a significant threat to the agents," T.J.
Bonner, head of the National Border Patrol Council and a 27-year
veteran of the agency, told The Washington Times.

In short, the violations don't appear to be "accidental." And if
Mexican army units are working in cahoots with drug smugglers, it
marks a nasty escalation in America's war on drugs.

Meanwhile, as these reports are coming out, states in the Southwest
remain under siege from immigrants crossing the border illegally. No
fewer than 300 immigration-related bills were considered at the state
level last year, and 36 of them were enacted, according to the
National Conference of State Legislatures.

The possibility of regular military incursions by Mexican soldiers
adds an ominous note to our already strained relations with our
neighbor to the south.

It should also make clear what too many still fail to see: Our border
appears to be an open sieve. The states are acting because the
federal government -- which has ultimate responsibility -- has failed to do so.

The question that remains is: Why?