These are the dictators who throw opponents in jail — or worse

The many antics of Donald Trump have made headlines throughout his wrecking ball of a presidential campaign, but he managed to cross arguably his most dangerous line yet at the second debate on Sunday night in St. Louis.

Trump, whose candidacy is on life support following the release of a video in which he brags about sexually assaulting women, threatened to jail Hillary Clinton if he wins the presidency.

"I hate to say it, but if I win, I am going to instruct my attorney general to get a special prosecutor to look into your situation," Trump said, referring to Clinton's use of a personal email account while she was secretary of state.

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Say what you will about whether the United States is a true democracy, the threat of jailing a political opponent is still not something done in a democratic system.

It is, however, something done by the leaders of dictatorial states around the globe, as listed below.

Vladimir Putin, Russia

Putin, whom Trump has praised as a strong leader, is one of the starkest examples of a politician willing to do just about anything to eliminate anyone who represents even possible opposition.

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Mikhail Khodorkovsky, whom The Economisthas called "the Kremlin's leading critic in exile" is a former Russian oligarch jailed for a decade in Putin-controlled Russia on charges that critics of the Kremlin have called politically motivated. Now living in exile in Switzerland, the Kremlin is again trying to put Khodorkovsky behind bars.

In 2006, a Putin political adversary named Alexander Litvinenko was poisoned to death, and experts pointed their fingers at the Kremlin.

Garry Kasparov -- the famed chess champion turned politician, human rights champion, and Putin critic, as seen in the Tweet above -- is also living in exile after helping to lead protests against Putin in Russia years ago.

Another key figure in those protests, Sergei Udaltsov, is currently serving a 4.5 year jail term on charges of plotting to overthrow the Kremlin.

Boris Nemtsov, a political reformist and yet another key leader in those protests, was shot dead last year. And, while definitive evidence pointing at Putin or his cohorts has not come out, as The Guardianput it, "Critics of Vladimir Putin have an uncanny habit of ending up dead."

Viktor Yanukovych, Ukraine

Former Prime Minister Viktor Yanukovych, who has strong admiration for Putin and fled Russia during the 2014 revolution in Ukraine, had former Prime Minisiter Yulia Tymoshenko thrown in jail on corruption charges.

She was sentenced to seven years, of which she served three years.

Nicolás Maduro, Venezuela

Venezuelan political opposition leader Leopoldo Lopez was thrown in jail in February, 2014, then sentenced 1.5 years later to 14 years in prison on charges of inciting violence at an opposition rally during which he called for calm demonstrations.

Many observers, including the attorney who prosecuted the case, have said the case was entirely fabricated.

The military junta of Myanmar

The party of Aung San Suu Kyi easily won a parliamentary majority in 1990, but it would take decades before she was able to lead the government.

Instead, the ruling military junta acted as though the election had not taken place, and the 1991 winner of the Nobel Peace Prize found herself under house arrest on and off for years.

In 2015, the first open election since the one in 1990, her party again won handily.

Kim Jong-un, North Korea

Supreme Leader Kim Jong-un doesn't have political opponents in a traditional sense. No one is running against him in an election.

But isolated leaders looking to consolidate power can find enemies in many places, real and imagined.

Whatever the truth may be, the supreme leader has seen it fit to execute several high-level North Korean officials, including the deputy premier for education and Kim Jong-un's own uncle -- then the second-ranking party official Jang Song-thaek, who was accused of plotting to overthrow the government via a military coup.

Ali Khamenei, Iran

Ayatollah Khamenei, the supreme leader of Iran, allegedly directed the detention of opposition leaders in 2011, two years after they opposed Mahmoud Ahmadinejad in the 2009 election in which Ahmadinejad won the presidency.

Ahmadinejad's election was followed by huge protests during which demonstrators alleged the president had won via voter fraud.

Yoweri Museveni, Uganda

Kizza Besigye, who used to be the doctor of President Yoweri Museveni, has been beset by legal challenges thrown at him ever since he became Museveni's primary political opponent.

Besigye was placed under house arrest leading up to the 2016 election, preventing him from holding political rallies.

As votes were rolling in, he was arrested yet again.

Then, after losing the election, Besigye was charged with treason.

Museveni, who has now begun his fifth term in office, has been accused of winning the election via voter fraud.

Robert Mugabe, Zimbabwe

President Robert Mugabe ordered the arrest of opposition leader Morgan Tsvangirai before the results of the 2008 election had come in.

Tsvangirai was reportedly tortured while under arrest, as were his supporters.

Hun Sen, Cambodia

Opposition leaders in Cambodia face a range of charges as political tension there ramps up ahead of local elections in 2017, which in turn will set the stage for national elections the following year.

In one of the most high-profile politically-motivated moves, the government of Prime Minister Hun Sen ordered the arrest of Cambodia National Rescue Party deputy leader Kem Sokha on charges having to do with an alleged mistress.

He was sentenced to five months in jail, though he is appealing the decision.

Hosni Mubarak, Egypt

Former President Mubarak, now 88, had ruled Egypt for well over two decades when he jailed opposition leader and then-presidential candidate Ayman Nour after a 2005 election in which Mubarak won 88.5 percent of the vote.

Nour was accused of forging the petition signatures he needed to form his opposition party.

Mubarak himself was jailed in 2012 after his government was overthrown, and currently spends his life under close watch at a military hospital in Cairo.