False Flag...There are a few meanings/definitions for false flag.
One is a flag flown to disguise the nationality or affiliation of a vessel, vehicle, or base of operations. For example if a pirate ship flies the flag of one country and attacks the vessels of another country, there is a good chance that the country being attacked will retaliate and attack the innocent country who's flag was being flown.
90 years ago, the German parliament building was burned down due to arson. Immediately after, the Nazis passed a piece of legislation called "decree for the protection of state and people" giving them total police state control over the people.
The fires were blamed on Hitler's political rivals, however historians believe that is was actually the Nazi party who started the fire in a plot to control the masses through fear.
In 1939, Hitler needed a reason to attack Poland and staged a false flag by dressing German troops in Polish uniforms pretending to attack a German radio station near the border. He used concentration camp inmates who had been previously shot and dressed them in German uniforms, leaving them at the station to make it appear they were attacked by the Poles. This created the excuse for Germany to start WWII.
False flag operations can be done on air, land or on the sea and do not have to be military operations, but can be business dirty tricks or political scams.