Well folks, that's what Lewis Lee Millett did. That and much more. The United States has to be very proud of this hero.
And so does Canada!

But soon after joining up the US president made an announcement that there would be no American blood shed in the war going on in Europe. The US position at the time did not involve "boots on the ground" to supress Hitler's advances on the free world.
Livid at the announcement, Millett deserted his post and hitchiked to the Canadian border with a friend who had just been released rather shamefully from the US military. Their plan was to join the Canadian army and head off to war. But Canada had other plans. It refused entry into the country to these teens..both in uniform. So the boys returned home, got a change of clothing, using the uniforms to again aid in the treck back to the border. Millett's friend turned back just before getting to the border. Stopping just short, Millett decided to bury his uniform, don civilian clothes and then try the entry. It worked. (Years later Millett tried to find the uniform and couldn't. ) After being accepted in the infantry, he was sent off to a New Brunswick recruit training camp. Here his basic infantry training included bayonet training that he had not yet had in his American service. Training that would become critical in his years to come.
Soon word came down that he had been selected with a few others who were to be shipped off to Ottawa for some very special top secret training involving a new invention they called Radio Detection and Ranging. Today we simply call it... RADAR. Successful completion of this soon saw Millett sent off to England where he became involved in anti-aircraft radar duties. While In London, the American government finally decided to enter the war effort. Millett then switched back to the US uniform and found himself enroute to Aftrica, where within short order he became a war hero... for the first time.
When a loaded tanker of fuel caught fire near a large body of troops, he jumped in and drove it off a safe distance and jumped out just before it blew up. He would be awarded the Silver Star for this bravery. While there he no doubt called upon his anti aircraft training in Canada when he shot down a plane from the back of a truck.
But then his war record caught up with him. The authorities finally realized that he had deserted his post back in the United States, but now they had a problem. What to do with a war hero deserter who was just promoted to Sergeant? So after much thought, they tried and convicted him and gave him about a $50 fine and told him not to do that again. He didn't. Weeks later he was commissioned a 2nd Lt.
After WWII Millett returned home and went back to school, and after three years was called up for service in Korea. Now commissioned as a Lieutenant, he would learn as a platoon commander that the enemy thought the Americans were not brave enought to get involved in hand to hand combat. Infuriated with the insult, he took every chance he had to practice his platoon in bayonet tactics, whilst most around him thought he was a little strange.
At Hill 180 Millett's platoon came under heavy enemy fire. He decided he must do an uphill bayonet charge and led the way to a victory by having the entire platoon engage in hand to hand combat and the tossing of grenades that left the hill scattered with about 50 enemy dead and the rest retreating. At least 20 had bayonet wounds. Millett would be awarded the Distinguished Service Cross for this. He would repeat the process a few weeks later and this time would be awarded the Medal of Honor.
Still later in Vietnam, Millett would act as a military advisor and intelligence officer and would play a major role in setting up commando schools both there and back in the US. He would retire in 1973 as a full colonel and passed away a few years ago.
I had the piviledge of meeting Colonel Millett's son and daughter-in-law whilst attending Millett's funeral at Riverside Cemetery in California, at their invite. I further visited the family home and felt like I was sitting in a military museum with pictures of the Colonel with several presidents and letters of best wishes from several generals all around me. When asked where his office was, I had a shutter go up my spine when told I was sitting in it... being the livingroom chesterfield, and exactly where I was sitting.
I was permitted to see and hold his Medal of Honor and other medals but the family insisted I go through a medal detector before leaving the house... hehe.

Millett was very proud of the fact that he was court-marshalled and also went on to earn the Medal of Honor. He was equally proud of the fact, and often made note in conversations, about the fact that it was his Canadian training on the bayonet that led to the instruction he could then pass on to his platoon, and resulted in part for their incredible heroism in Korea.
He was also very proud of the three service medals Canada awarded him for his stint in the service in our military. While the US Government would not allow him to hang the Canadian medals on his uniform, he apparently wore them anyway... hidden under the yank ones held in place by velcro ... so the story goes.
Millett's son Lee Jnr is also a courageous Vietnam veteran and actually served at the same time as his father. On return to home Lee Jnr was commissioned as a sculpter to create a lasting memorial, which is now a National Memorial at Riverside for those POW's and MIA's from that war. Many missing to this day.
Another son served with honor in the 101 Airborne and lost his life with 255 other passengers on a flight returning from peace keeping duties and hoping to be home for Christmas with family and friends. The nation and the 101 Airborne lost 236 heroes that day. It was the worst airborne accident in Canadian history. It's causes are still in dispute.
If the Colonel is reading this today, happy birthday sir. All North America salutes you today, on what would have been your 92nd birthday. That's a lot of candles sir!
Bart