On Sunday, President Trump asserted that he may declare a national emergency in order to secure funding to build a controversial wall on the southern border. Following Trump's comments, some Americans may want to know whether Obama ever declared a national emergency. Trump's potential declaration wouldn't be unique per se, as his predecessor declared many national emergencies during his tenure. However, declaring a state of emergency for the sake of building a border wall is perhaps more controversial than Obama's national emergencies, CNN suggested.

On Jan. 6, the president made it clear that he was strongly considering making an emergency declaration. "I may declare a national emergency dependent on what's going to happen over the next few days," CNN noted he told reporters at the White House. Trump has the authority to declare a national emergency under the 1976 National Emergencies Act. This law essentially allows a president to define what he believes constitutes a national emergency and subsequently make a related declaration, the Washington Post reported. This declaration then allows the president access to specialized funds via certain emergency laws.

All recent presidents going back to Jimmy Carter have declared at least one national emergency during their time in office, CNN noted. For his part, Barack Obama declared 13 national emergencies, with many of them focused on international affairs and containing foreign conflicts, the outlet reported.

For example, in 2012, Obama declared a national emergency entitled, "Blocking Property of Persons Threatening the Peace, Security, or Stability of Yemen" in order to freeze the assets of anyone perceived to be negatively impacting a political transition in Yemen, VOA reported. In 2014, the 44th president issued a national emergency referred to as "Blocking Property of Certain Persons Contributing to the Situation in Ukraine," which similarly locked the assets of those thought to be undermining democratic processes in Ukraine. These are just two of many internationally oriented states of emergency that Obama declared while in office.

For his part, Trump has thus far declared three national emergencies during his tenure, CNN reported. One centers on creating penalties for individuals around the world who are involved in human rights abuses. Another penalizes individuals involved in perpetuating violence in Nicaragua. And another imposes sanctions on foreign entities who seek to interfere in American elections.

While Trump can declare a national emergency with the intention of building a border wall, a court challenge or a congressional resolution blocking specific emergency powers could prevent him from moving forward with his plans, the Washington Post explained. Representative Adam Smith, the chairman of the House Armed Services Committee, echoed some of these sentiments when discussing Trump's potential national emergency plans on ABC's This Week, The Hill reported.

"In this case, I think the president would be wide open to a court challenge saying, where is the emergency?” the chairman asserted. “You have to establish that in order to do this. But beyond that, this would be a terrible use of Department of Defense dollars.” In reflecting on the prospect of a potential court challenge to a national emergency declaration, White House Press Secretary Sarah Huckabee Sanders said on Fox News Sunday that "Whatever action he [Trump] takes will certainly be lawful, and we’re looking at every option we can," The Hill noted.

If Trump declares a national emergency, it would constitute an action that certainly wouldn't be unique to his presidency. However, the subject of his potential forthcoming national emergency — the border wall — is perhaps more controversial than those of other presidents' national emergencies, and will likely face more significant scrutiny.