Article 1, section 9 of the Constitution states that:
The Privilege of the Writ of Habeas Corpus shall not be suspended, unless when in Cases of Rebellion or Invasion the public Safety may require it.

The Constitution is specific about the circumstances under which law enforcement (including the United States military) operate without judicial oversight. Simply put, there needs to be a state of “Rebellion or Invasion” to even consider it.
If President Donald Trump thinks that a state of Rebellion exists – this is sufficient to declare martial law across The United States and the President would need to have the cooperation and participation of the military forces.
In 1878, United States Congress passed the Posse Comitatus Act, which prohibits federal military forces from participating in domestic law enforcement activities without authorisation by United States Congress.
But the US military can freely participate in domestic operations with no legal consequences. Take for instance, following sophisticated terrorism—highlighted by the 1993 World Trade Center bombing and the 1995 Oklahoma City bombing—the armed forces supplemented and assisted local and federal law enforcement agencies in the operational, logistical, and technical aspects of anti-terrorism.

The military’s anti-terror responsibilities during “special security events” provide the best example of this role. It has become commonplace for the armed forces to help secure high-profile targets from terrorist attacks, such as the Super Bowl and presidential inaugurals.
The military services’ abilities or importance at these venues, especially considering the range of threats that terrorists pose when targets are not only high-value but concentrated. Military troops (including the National Guard) always serve a “secondary” role in these deployments, neither replacing local police nor enforcing civil laws, such activities are within the limits of Posse Comitatus.
So President Trump can theoretically declare the country to be in a state of Rebellion and therefore subject to martial law, his declaration will not have force unless Congress goes along with him and decides to send in the US Army and US Air Force. The US Naval forces, which includes the US Navy, US Marines, and US Coast Guard, are not covered by Posse Comitatus, though the Navy and Marines have internal policies that produce the same effect.
National Guard units, are State forces not Federal, so Governors can use the National Guard to impose martial law within their states should they need to.
President Trump can also use the Executive order by President Obama from 2012:
You can read this on the White House Website. Highlights include:
Policies relating to a Draft
The Secretary of Labor, in coordination with the Secretary of Defense and the heads of other agencies, shall upon request by the Director of Selective Service, and in coordination with the Secretary of Defense, assist the Director of Selective Service in development of policies regulating the induction and deferment of persons for duty in the armed services.
The Creation of a National Defense Executive Reserve
The Secretary of Homeland Security will establish a National Defense Executive Reserve (NDER) and be responsible for recruitment, training, monitoring, and activation of NDER units in times of a national defense emergency.
Americans need to understand that Martial law has been in effect in the United States during several periods of its history where a region or the United States as a whole are placed under the control of a military body.
On a federal level, only the president has the power to impose Martial Law. In each state the governor has the right to impose martial law within the borders of the state.
In the United States, martial law has been used in a limited number of circumstances, such as directly after a foreign attack, such as Hawaii after the Japanese attack on Pearl Harbor or New Orleans during the Battle of New Orleans; after major disasters, such as the Great Chicago Fire of 1871 or the San Francisco earthquake of 1906; local leaders declared martial law to protect themselves from mob violence, such as Nauvoo, Illinois, during the Illinois Mormon War, or Utah during the Utah War; or in response to chaos associated with protests and mob action, such as the 1934 West Coast waterfront strike, or mob actions against the Freedom Riders.
The martial law concept in the United States is closely tied with the right of habeas corpus, which is, in essence, the right to a hearing on lawful imprisonment, or more broadly, the supervision of law enforcement by the judiciary. The ability to suspend habeas corpus is related to the imposition of martial law.
Remember what we started with: Article 1, Section 9 of the US Constitution states, “The Privilege of the Writ of Habeas Corpus shall not be suspended, unless when in Cases of Rebellion or Invasion the public Safety may require it.”
There have been many instances of the use of the military within the borders of the United States, such as during the Whiskey Rebellion and in the South during the Civil Rights Movement, but these acts are not tantamount to a formal declaration of martial law.
The distinction must be made as clear as that between martial law and military justice: deployment of troops does not mean that the civil courts cannot function, and that is one of the keys, as the Supreme Court noted, to martial law.
In United States law, martial law is limited by several court decisions that were handed down between the American Civil War and World War II. In 1878, Congress passed the Posse Comitatus Act, which forbids military involvement in domestic law enforcement without congressional approval.
Throughout United States history, several examples of the imposition of martial law, aside from that during the Civil War and if anything the United States as a whole today is in a better position for the implementation of Martial Law by the United States President.
The whole point of martial law is that the guy with the guns makes the rules and Americans like guns and also strong leaders.

How to trigger a martial law?
Terror attacks? Riots? Rebellion?
If these are statewide the National Guard can enforce a curfew initially. But if there is something taking place in multiple states and the federal government agencies such as the Federal Bureau of Investigation and US Intelligence and state-wide police cannot handle then the President may be able to declare martial law – he doesn’t require the United States Congress to authorise something that will take time, he is the leader and has the power to suspend…
In the United States, a parallel legal regime allows President Trump to sidestep constraints that normally apply. The moment the President declares a “national emergency”—a decision that is entirely within his power more than 100 special provisions become available to him.
President Trump can, with his pen, activate laws allowing him to shut down many kinds of electronic communications inside the United States and freeze Americans’ bank accounts. Other powers are available even without a declaration of emergency, including laws that allow the president to deploy troops inside the country to subdue domestic unrest – in effect Martial Law!

Americans need to understand that whenever a President (or a Governor of a State) sends US troops to enforce rules that are any different than the normal ones, that is martial law.
President Truman sent in the troops during the Korean War to deal with steel production but that got struck down by the Supreme Court, and Truman backed down – President Trump may need to consider ways of dealing with the United States Supreme Court as well as United States Congress today that in effect can neutralise there effectiveness before declaring A State of Emergency or Martial Law!
During World War II, Americans locked up Americans of Japanese ancestry in or near military camps and they got away with it at the time, and that is what martial law will look like in the United States should it be initiated.
Remember, the United States military – here I am talking of the Army and Airforce – alongside state-based National Guard units have literally hundreds of bases across the United States each can easily house between 1,000 to 5,000 civilians in a national emergency and this translates to say (300 bases across the US) 300,000 to 1.5 million Americans who can be detained should it be required – remember also that the United States is NOT a Democracy but a Republic and to an extent an Oligarchy with privatised prisons – currently there are some 3 to 5 million Americans in prison and or on licence!
US private prisons can assist the United States government and military in opening their facilities to hold a further 1.2 million Americans whilst the State of Emergency is in process.

Can the President do this nationwide?
Of course, he can, he is the Commander in Chief of the Armed Forces! And only needs a few of his senior generals to go along with it.
Politically? Americans will be more compliant towards the United States Armed Forces than they would be towards the police or the FBI and once Martial Law in effect they will follow. The interesting areas we haven’t researched on are the armed militias in the US – most currently support the United States President and they may feel he is correct and will work with local law enforcement to crack down on those opposing the state of emergency – naturally these militias once used for the purpose of identifying local troublemakers will need to have their leaders arrested and militias disbanded as they can cause problems down the line.
Legally: The President can declare a State of Emergency, which allows the mobilisation of the National Guard as a start.
The State of Emergency doesn’t suspend the Constitution. But has to be renewed every year to stay in effect.
Remember: The United States is already in a ‘Soft State of Emergency‘ look at the militarisation of the police forces at the state level.

In theory, Congress is supposed to declare martial law before the President could impose it. The Posse Comitatus Act states that the armed forces can’t be used to enforce domestic laws without Congressional approval.
But there are loopholes/ exceptions where President Trump can just go ahead and do stuff because Congress has said they’ll trust the President’s judgment where states of emergency were put into effect – remember President Clinton (Oklahoma bombing), President Bush (9/11), President Obama…
Congress declared martial law during the Civil War, President Lincoln imposed it and suspended the writ of habeas corpus on his own initiative. Which got struck down, and Lincoln nearly had the judge arrested.
In the end, everyone backed off. The writ was not enforced, but the judge wasn’t arrested.
Short answer? The President could declare whatever he wanted, but whether anyone would listen to him is another question and Americans may be breaking some laws if they didn’t obey The President – this area needs to be researched!
Anyway back to the Question: Can President Donald Trump declare Martial Law in the United States of America?
Answer: Yes He Can!

http://www.facebook.com/MohammedAbbasi
http://www.linkedIn.com/MohammedAbbasi
http://www.youtube.com/AbbasiOfficial
Mohammed Abbasi