What You Need to Know About Turkey's Political Landscape Amid Attempted Military Coup

— -- Amid an attempted coup in Turkey, here’s a look at the fraught political landscape of the country that is often called “the bridge between East and West.”

Who’s in Charge?

If a coup is indeed underway, it would be the fourth time in Turkey’s modern history that the military has seized power.

It would also mean that military officers have supplanted President Recep Tayyip Erdogan, the democratically elected president of the country who has ruled over the country as Prime Minister and later president since 2003.

What Role Has the Military Played in the Past?

The Turkish military has a history of seizing power when it feels that the country is heading in a wrong direction.

Previous coups in 1960, 1971 and 1980 saw the military -- the second largest among NATO countries, after the U.S. -- seize power or affect change in one way or another.

What Is the Security Situation in Turkey Like?

Throughout the 2000s, Turkey was seen as a stable, prosperous country. Tourism boomed, as foreigners perceived the country to be a safe place to gain exposure to Middle Eastern culture and history.

However, in the past few years, several attacks have taken place throughout the country, largely perpetrated by Islamic and Kurdish extremists.

Just last month, an attack at the main airport in Istanbul -- the country’s most famous city -- left more than 40 people dead. The Islamic State was suspected to be behind the attack.

What Are Relations With the U.S. Like?

Turkey’s location -- wedged between the Middle East and Europe -- lets it wield considerable influence, and the country is a major U.S. ally. It has been a NATO ally since 1952.

It is arguably the most important ally that the U.S. has in the fight against the Islamic State in Syria, and is home to Incirlik Air Base.

Earlier this year, the U.S. government ordered the families of U.S. military personnel to leave the base -- from where the U.S. launches strikes in Syria.

A senior U.S. defense official told ABC News that a total of 2,200 U.S. service members and civilian employees of the Department of Defense are in Turkey. The official added that from that number, 1,500 US personnel are at Incirlik Air Base.

However, President Erdogan draws the ire of many in the U.S. During a visit to Washington, D.C., in April, scuffles broke out at a think tank in Washington where the leader was visiting.

The U.S. also provides refuge to Fethullah Gulen, a moderate Turkish cleric living in self-imposed exile in Pennsylvania. President Erdogan has accused Gulen of leading a parallel, shadow state.

How Are Americans Living or Visiting Turkey Affected?

The U.S. State Department's country information has warned that: "Due to a record of past terrorist attacks in Turkey and a continuing threat from both transnational and indigenous groups, the threat level for the possibility of further terrorist attacks against U.S. citizens and interests remains critical."

As the coup attempt is unfolding, the State Department is tweeting advice and updates for Americans.

The department's official account has advised Americans in Turkey to contact their families and shelter in place. The account has also provided some news updates, including a tweet saying: "Martial law and a curfew have been imposed in Turkey."

Officials are advising Americans who have not heard from loved ones living in Turkey to contact the State Department for assistance.