Among President-elect Donald Trump's plans to implement the largest deportation operation in U.S. history is a promise to use the military as the centerpiece of that strategy. Trump signaled that he would declare a national emergency and mobilize military resources to carry out large-scale deportations, facing logistical, financial and legal challenges associated with the measure, according to CBS News.

While federal law restricts the use of military personnel in domestic law enforcement activities, Trump and allies are considering invoking the Insurrection Act of 1807, which allows exceptions in cases of "rebellions" or crises that hinder normal law enforcement. The proposal includes the use of military transport to transfer migrants, the construction of temporary detention facilities and operational support for Immigration and Customs Enforcement (ICE). Experts, however, warn of the legal and political risks of the initiative, including possible violations of the Posse Comitatus Act and impact on public trust in the military.

“Trump declared a national emergency at the border during his first administration, after Congress declined to fund border wall construction. He used the declaration to unilaterally divert Pentagon funds to expand the border wall”, according to CBS.

The estimated cost of the operation, which involves the deportation of 1 million people a year, is $88 billion annually, exceeding the resources available in the Department of Homeland Security's budget. The financial and operational feasibility, in addition to ethical and legal issues, makes the proposal controversial. According to the publication, critics highlight the increase in political polarization and the possibility of judicial challenge, arguing that the application of the Insurrection Law in such circumstances would be unprecedented and potentially illegal.