Can we get by without them?
Some years back, there was a call for undocumented immigrants in the United States to boycott work in protest of proposed increased criminal sanctions against such immigrants.
The boycott was intended to illustrate the role that the immigrant workers play in the American economy. Some owners of businesses in metropolitan areas felt a financial loss on that day and the customers of those businesses were inconvenienced, but the tactic was generally regarded as a flop and hasn't been repeated.
The work that immigrants do has been referred to as "work that no one else is willing to do." This is an exaggeration, both in the assumption that no American citizen will do menial labor and the assumption that no illegal immigrant does anything other than menial labor. Still, as generalizations go, it is close to being accurate.
Deporting the estimated 11 to 12 million undocumented immigrants would be impractical, but imposing severe sanctions on the employers of such immigrants might be effective in reducing the incentive for the undocumented workers to come to the U.S. or remain in the country.
If we lost most of them suddenly, it would have a jarring effect on the nation's economy. A change in labor availability would create a variety of short and long-term losers.
Without a pool of cheap labor, some jobs will not get done and others will only get done at a higher cost to consumers. If a major source of cheap labor dried up, that would affect all companies that rely on low wages, even those that don't hire illegal immigrants.
Restaurant food would become more expensive, and there would be fewer restaurants. There would be a similar weeding out of other businesses in the service sector. People would have to do more things for themselves, particularly those of the upper middle classes who would have to forgo the luxury of servants.
Agricultural products, particularly processed meats, would become more expensive as would many other processed or manufactured goods.
However, along with the losers, there would be winners. Without a pool of cheap labor, the base wage for menial labor would increase. As the standard of living for laborers increased, that would create demand in other segments of the consumer economy. The tax base of wherever they lived would improve.
When a society places a high value at the entry level on the labor of most of its citizens, then the society as a whole is more prosperous than it otherwise would be. This is a philosophy that served America well for much of its existence but it is a philosophy that has slowly eroded over the last few decades.
By accepting a large pool of cheap labor, we are accepting the widening gap between the 'haves' and the 'have nots' in our society and our similarity to an underdeveloped nation grows.