Which agency focuses specifically on immigration enforcement under DHS?

The U.S. Immigration and Customs Enforcement (ICE) is the agency that specifically focuses on immigration enforcement under the Department of Homeland Security (DHS). ICE's primary role includes investigating and enforcing laws related to immigration and customs, including the apprehension of individuals who are in the United States unlawfully. This enforcement aspect includes a wide range of activities, such as removing individuals who have violated immigration laws and conducting investigations into violations of immigration statutes.

In contrast, the other agencies listed have different focuses: the Federal Bureau of Investigation (FBI) primarily addresses national security and criminal threats, while the Department of State (DOS) primarily handles diplomatic relations and issues related to foreign affairs, including visa processing but not enforcement. Customs and Border Protection (CBP), while also part of DHS and involved in border security, primarily deals with the enforcement of laws related to entries at ports of entry rather than focusing entirely on immigration enforcement. Thus, ICE is crucial when it comes to the enforcement of immigration laws throughout the United States.