The world's largest immigration detention system is on the cusp of explosive growth as President Donald Trump pursues his signature campaign promise of mass deportations. The deportations represent a potential bonanza for private prison companies and a challenge to the government agencies responsible for the orderly expulsion of immigrants. Some critics say the administration's plans also include a deliberate attempt to isolate detainees by locking them up and holding court proceedings far from their attorneys and support systems. The Immigration and Customs Enforcement agency is starting to scale up from its current budget for about 41,000 beds to 100,000 beds.