Both.

The Wilson/Coolidge Era was nightmarish for immigrants, with a host of laws targeting East Asian migrants and displacing uncountable numbers of industrial workers particularly along the West Coast.

Eisenhower's Operation Wetback set off a wave of police terror along the Gulf Coast, crippled the agricultural economy, and killed hundreds of migrants forced into transit.

The current border policy funnels hundreds of thousands of migrants through an inhospitality Texas/Arizona desert region that's killed around 10k-50k people in the last decade.

None of it actually curbs immigration. It all just becomes a black market affair, affording employers a tool to depress wages and cartels an opportunity to press-gang border residents into cattle slavery.