SIERRA BLANCA, Texas -- In a swampy corner of his desolate ranch, Bill Addington proudly flouts the law.

The Department of Homeland Security has demanded that he tear down a rickety footbridge from his land across the Rio Grande into Mexico. Since the Sept. 11 terrorist attacks, authorities have shut down nearly a dozen of these informal river crossings along the Texas border. This is the last they know to be operating. They want it gone. Mr. Addington refuses.

He crossed that bridge countless times as a boy, darting into Mexico to buy candy or watermelon juice or to flirt with the girls at church-hall dances. Mexicans crossed over, too, every day, to work the cotton fields for Mr. Addington's father -- a U.S. Border Patrol agent. After a hard season's labor, they would all celebrate together with a night of bilingual poker, fueled by whiskey and calf-brain stew.

Mr. Addington, who is 52, clings to those memories. So when the Department of Homeland Security sent his family a letter this past summer warning that his bridge could allow "the illegal entry of terrorists, aliens, and/or drug traffickers," he scoffed.