5 times Americans left to fight in foreign wars

In the past few years, dozens of veteran and civilian Americans left the comfort and safety of their homes to tackle what they saw as an unspeakable evil growing from the Middle East — the Islamic State. A television documentary series from History followed those Americans as they fought with Kurdish fighters in Syria. The show pulls no punches in showing what combat looks like on the front lines of the fight against the world's most ruthless terrorists.

Read on and learn about how and why Americans fought the good fight long before their country was ready."I heard the stories, I knew that ISIS was evil," says PJ, a Marine Corps vet who served in Iraq. "But you can never understand the brutality that they're capable of until you see it with your own eyes... Most people in America aren't able or willing to come over here," he says. "And for them, I will carry what weight I can."

The group that came to be dubbed ISIS by Americans came to global recognition in 2014 while capitalizing on power vacuums in Iraq and Syria. The group managed to capture large swaths of both countries. In Iraq, ISIS captured most of Fallujah, took the provincial capital of Mosul, and even approached the outskirts of Baghdad.

In Syria, ISIS occupied most of the country's eastern half, basing out of the group's de facto capital, Raqqa. At the height of its power in 2014, the would-be terrorist state controlled the lives of some 10 million people. What was most horrifying about life under ISIS control was not only the restrictions on personal freedoms for those 10 million people, but the punishments for breaking ISIS law, executions of political prisoners and POWs, and the genocides committed against "apostate" ethnic groups, especially Yazidis.

Horrified by the ongoing violence, many American veterans of the war in Iraq were inspired by the dogged resistance of the Kurdish Peshmerga as they fought to push back the dark tide of ISIS' brand of Islamic extremism. The Peshmerga has long been the most effective fighting force in the region and a natural U.S. ally against ISIS.

Long before that alliance was solidified, and long before other regional powers, like Iran and Russia, decided to intervene in the two countries, some American veterans decided to travel to Iraq and join that fight alongside the region's only remaining stand against terrorist domination. For them, they would be fighting the good fight and doing the right thing against the wishes of the U.S. government and military. They fight unpaid and unsanctioned. Worst of all, they face jail time if they're caught by Americans — execution if they're caught by the enemy.

But the Islamic State isn't the only evil Americans fought before their country was ready.

Named for the Marquis de Lafayette, a French general who was instrumental in the success of the American Revolution, the Lafayette Escadrille was a squadron of American airmen who volunteered to fight for the French against Germany in the first world war in 1916 – almost a full year before the United States entered the war on the side of the Entente.

For three years, Poland fought Soviet Russia for control of parts of Eastern Poland and Ukraine. American volunteers, wary of the spread of Communism to the West, volunteered for the Polish Air Forces against the Soviets with notable successes — the Soviets put half-million ruble bounty on one aviator's head. One Polish general said of the Americans,

Fascism was the true enemy in Spain, where those loyal to the democratic Second Spanish Republic fought Francisco Franco's nationalism for three years before their defeat in 1939. Nazi Germany and Fascist Italy were among the countries who officially supported the Nationalists, while the Soviet Union supported the left-leaning Republicans. Meanwhile, Britain and the U.S. officially stayed out of the fighting.

Many, many volunteers poured in from all over the world to fight for the Republican army in the International Brigades. For the Americans, they joined what was known as the Abraham Lincoln brigades, an amalgamation of English-speaking British and American volunteers.

The early days of World War II were dark days for the British. The threat of Nazi invasion loomed large over the whole of the island. We know today that they were relatively safe across the English Channel, but they hardly thought so back then. But after the seeds of our "special relationship" with the United Kingdom were sown in World War I, many Americans eschewed American neutrality to join the RAF in giving Jerry a black eye.

Those men would join the RAF's three Eagle Squadrons. The first was formed in September 1940 and fought with the British until their units were transferred to the U.S. 8th Air Force in 1942.

A truly joint operation, the Flying Tigers were formed from a bold group of Army, Navy, and Marine Corps airmen and placed under the command of a retired American general attached to the Chinese Air Force. Three squadrons of 90 aircraft trained in Burma well before the U.S. entry to World War II. So, when their first combat mission came calling just 12 days after the attack at Pearl Harbor, they were more than ready.

When the U.S. came to take them back, they were made part of the U.S. Army's 14th Air Force – the 23rd Fighter Group. The 23rd still flies planes with shark teeth nose art on their A-10 fleet, an homage to the P-40 Warhawks flown by the Flying Tigers.