The absurdly dysfunctional agricultural sector is a prime example.
Up to two-thirds of the workforce tending to crops and livestock at least 1 million current workers are undocumented, up from a third in the mid-1990s. Many are relatively skilled, most have been in the country for a decade or more, and some have moved up to jobs in middle management.
Despite their central role in providing the country's food, they remain subject to harassment, raids and deportation.
Farmers and ranchers have complained about this for years, warning that the shortage of native-born workers willing and able to do agricultural work, along with the threats to migrant labor, would put farmers out of business and shift crop production overseas.
Their increasingly dire pronouncements have been met by the usual right-wing rhetoric attacking "amnesty" for illegal workers.
At the same time, the creaky visa system designed to supply agribusiness with foreign guest workers is widely seen as a failure bureaucratic, inflexible and incapable of meeting time- and weather-sensitive labor demands. By the time guest workers are issued visas, it's often too late.
The results are that relatively few employers rely on the program and farmers struggle with chronic labor shortages.
Past attempts at a standalone fix have failed in Congress, lacking unified support from agribusiness and farm workers. But employers and unions forged a deal just in time for inclusion in the Senate immigration bill.
Their pact would grant legal status through so-called Blue Cards for undocumented farm workers, who could become permanent legal residents in a sped-up five-year process. The guest-worker visa program would be scrapped in favor of a new system to provide up to 337,000 visas over three years for foreign farm workers. Unions got a relatively tight cap on visas (though it could be adjusted in the future by the agriculture secretary) and a requirement that employers pay for migrants' housing and transportation to and from the job. Employers mostly held the line on wages.
It's in no one's interest to saddle farmers and ranchers with an unstable workforce and labor shortages that threaten the supply of domestically grown crops. The agricultural provisions in the immigration bill would go a good distance toward fixing that. And as part of the overall immigration legislation, it may generate support for the bill from some rural lawmakers who would otherwise oppose it.