If the US wanted to instill Martial Law on the populace what would be their best method to catch the populace by surprise, or dupe them into embracing it if they can’t be ambushed into it?

Some people who are old enough or near old enough to have lived or fought in WWII mention how sly the Nazis were in setting up all the pieces then cracking down on the Jews, to the point some of the Jews did not even realized what happened to them until they got off the train car. If the US government wanted to install Martial Law, what method would they use, guile, making people think it was something else going on or that it was something to help the public, like battling terrorist, would they just be so stealthy that they can set it into motion right under the populace nose, or would they make anyone who got wind of the plan look like an idiot as to insure apathy of the populace?