Immigration Raids vs Employers

The new pro-immigration ploy is to "go after employers" rather than conducting raids on work places. How does that help illegal immigrants? It is first necessary to "prove" immigrants are being hired illegally before the employers can be indicted. This is hard to do without nabbing illegal immigrant workers first. Every time a method is found to be effective a reason for not using it is promoted. Fences work, so the pro-immigration lobby says it doesn't. Raids work, so raids are said to be inhumane and against people's civil rights. Using the National Guard to protect the border works, so it becomes an affront to Mexico; and the list goes on.
There is a lot of money involved--lower wages, drugs, immigration lobby etc. Everyone is heard except the American people.