The scrutiny of President Donald Trump has been high this week as U.S. officials have traded threats with North Korea, including the president’s famous vow to send “fire and fury” to the north Asian nation if necessary.

This comes just weeks after Pyongyang tested an intercontinental ballistic missile believed to be able to reach the U.S. mainland and days after reports that the nation had successfully produced a miniature nuclear warhead that can be delivered by missile.

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Trump now wonders if that language was even strong enough, and added on Thursday that North Korea should be “very, very nervous.”

Dictator Kim Jung Un’s regime says it’s laying out a plan to strike the U.S. territory of Guam in response, and all eyes are on what Trump will do next.

On Wednesday, he retweeted two tweets which criticized President Barack Obama ’s strategy for dealing with North Korea and its nuclear program.

https://twitter.com/AmbJohnBolton/status/895343008580866050

https://twitter.com/TheFive/status/895451762122833921

So we decided to take a look back at exactly what Obama did about North Korea during his time as president, and also at the efforts of his predecessors, President Bill Clinton and President George W. Bush.

President Bill Clinton

Soon after Clinton took office in 1994, North Korea threatened to abandon its commitment to the Nuclear Non-Proliferation Treaty behind. North Korea refused an international inspection related to the treaty. This led the Clinton administration to seek to bring the nation back into the fold.

Former President Jimmy Carter was secretly sent to Pyongyang to pave the way for a diplomatic agreement.

Clinton’s administration successfully established a deal known as the Joint Framework Agreement which offered $4 billion worth of nuclear, energy, economic and diplomatic benefits in exchange for the halting of North Korea’s nuclear program in 1994. The deal also included two light-water nuclear reactors, which were believed to be more difficult to use to make weapons than Pyongyang’s plutonium reactor.

The International Atomic Energy Agency was set to oversee all of this and do routine inspections.

"This agreement will help achieve a longstanding and vital American objective -- an end to the threat of nuclear proliferation on the Korean Peninsula,” Clinton said at the time.

President George W. Bush

Bush famously named North Korea as one part of the three-part “axis of evil” with Iraq and Iran in his State of the Union speech as president in 2002.

“North Korea is a regime arming with missiles and weapons of mass destruction, while starving its citizens,” he said.

Later that year, the country confirmed what Bush said by admitting it had been secretly conducting a nuclear-weapons program for several years and proceeded to withdraw from its agreement with the Clinton administration shortly thereafter.

By 2004, U.S. officials believed North Korea had developed between two and eight nuclear weapons.

“The Six-Party Talks” comprising China, North Korea, Japan, Russia, South Korea and the U.S. began in 2003 and continued over a number of years until 2009 under President Obama. In 2005, the group offered some energy and economic assistance if North Korea would give up its renewed efforts to build up its nuclear program, which Pyongyang tentatively agreed to.

But that plan didn’t really hold and North Korea said it had successfully completed a nuclear test in 2006. In 2007, an agreement was reached to send $400 million worth of fuel, food and other aid in exchange for North Korea shutting down its main nuclear reactor.

Just before leaving office, Bush sent a personal letter to leader Kim Jong Il asking him to uphold his end of the bargain.

President Barack Obama

Obama had to deal with a nuclear test by North Korea in mid-2009. The U.N. Security Council quickly adopted sanctions banning arms transfers to and from the country.

Obama sent an envoy to North Korea at the end of the year, asking leader Kim Jong Il to begin denuclearization talks, but his regime didn’t make any major moves toward pursuing them.

Some more progress was made in 2012 when new leader Kim Jong Un agreed to halt nuclear tests in exchange for food aid.

North Korea’s pursuit of nuclear weapons continued, however.

Obama’s administration put the ball in North Korea’s court by outlining conditions it required before diplomatic negotiations could occur, but Jong Un’s regime has maintained for years that its nuclear program is necessary for defense.

He went as far as to threaten the “military might” of the U.S. in 2014 as debates over true capabilities of the North continued.

Last September, after yet another nuclear test, Obama said the U.N. and members of the original “Six-Party Talks” would “vigorously implement” those resolutions and that there were “consequences” for North Korea’s actions.

Before Obama left office, the U.S. led the U.N. Security Council to imposed sanctions on North Korea in November meant to slash its coal exports by 60 percent.

Email: abby.hamblin@sduniontribune.com

Twitter: @abbyhamblin