Trump's biggest accomplishments and failures as president as he heads into a reelection year after impeachment

In signing a $738 billion defense spending bill just a few days before Christmas, Trump officially established the sixth branch of the US Armed Forces — the Space Force.

The Space Force is the first new military service since the US Air Force was created in 1947.

Despite its name, the new branch has not been established to protect the planet from potential extraterrestrial threats, but is tasked with protecting the US military's assets in space.

"This is not a farce. This is nationally critical," Gen. John Raymond, who Trump tapped to lead the Space Force, told reporters earlier this month. "We are elevating space commensurate with its importance to our national security and the security of our allies and partners."

Many of the details surrounding the Space Force must still be ironed out. In many ways, the new branch is simply a more centralized version of military missions in space that already existed from the Air Force, Army and Navy.

Todd Harrison, who directs the Aerospace Security Project at the Center for Strategic & International Studies, recently told NPR: "It will create a centralized, unified chain of command that is responsible for space, because ultimately when responsibility is fragmented, no one's responsible."

Three years into his presidency, Trump's signature legislative achievement remains a Republican tax bill that made sweeping changes to the tax code — the Tax Cuts and Jobs Act.

As Business Insider's Joseph Zeballos-Roig recently reported:

• The law was the biggest overhaul to the nation's tax code in three decades, and the president pitched it as "rocket fuel" for the American economy.
• It permanently slashed the corporate tax rate to 21% from 35% while also providing temporary benefits for individuals and their families.
• Critics argued it was a windfall for massive corporations at the expense of the middle class. Meanwhile, supporters of the tax cuts contended it would unleash an economic bonanza. Businesses would invest in their operations, they said, resulting in improved worker productivity and higher wages.
• Treasury Secretary Steve Mnuchin, among others, said the law would juice the nation's gross domestic product to 3% (or more, as Trump said 6%) and soon pay for itself and spread prosperity.
• But the law has achieved none of the ambitious goals that Republicans put forward — and there are scant signs they ever will.

Trump signed the First Step Act into law in December 2018, marking the first legislative victory in years for advocates seeking to reform the criminal justice system.

The bill passed with overwhelming bipartisan support in Congress. It offers relatively modest changes to the federal prison system, but was praised as an important step forward by groups and activists seeking to end mass incarceration.

Business Insider's Michelle Mark summarized the key aspects of the legislation after it passed in the Senate last year:

• The passage of the bill...marked the first major legislative win in decades to address mass incarceration at the federal level.
• The bill overhauls certain federal sentencing laws, reducing mandatory minimum sentences for drug felonies and expanding early-release programs.
• The bill also makes retroactive a 2010 federal sentencing law reducing the sentencing disparity between crack and powder cocaine offenses.
• The bill also aims to lower recidivism by offering more rehabilitation and job-training opportunities, and it includes provisions intended to treat prisoners humanely — banning the shackling of pregnant inmates, halting the use of solitary confinement for most juvenile inmates, and mandating that prisoners be placed in facilities within 500 miles from their families.

ISIS shocked the world in 2014 when it took over a large swath of territory across Iraq and Syria and declared a caliphate.

The terrorist group's territorial holdings were the basis for its so-called caliphate, and provided it will a major base of operations to conduct attacks across the world.

After a five-year effort led by the US, ISIS's caliphate was finally defeated in March 2019.

Trump has at times falsely claimed that ISIS is totally defeated, embellishing the extent of the US military's success against the terrorist organization during his presidency. Though the terrorist group has lost its territory — its so-called caliphate — it's still estimated to have up to 18,000 fighters in Iraq and Syria.

In late October, a US raid led to the death of ISIS leader Abu Bakr al-Baghdadi.

Baghdadi was the world's most wanted terrorist up to that point and his death represented a major blow to the terrorist group.

"Last night, the United States brought the world's No. 1 terrorist leader to justice," Trump said at the time. "Abu Bakr al-Baghdadi is dead."

"Capturing or killing him has been the top national security priority of my administration," he added.

Trump's response to a deadly neo-Nazi rally in Charlottesville, Virginia, remains one of the most controversial moments in his presidency.

It was emblematic of Trump's struggle to bring the country together after tragedies, and more generally. His response also typified his controversial record on race relations and white supremacy.

Trump blamed "many sides" for the violence at the rally, which resulted in the death of a counterprotester, Heather Heyer. He later said there were "very fine people on both sides."

The president was excoriated by Republicans and Democrats alike over his response and his failure to offer a swift and forceful condemnation of white supremacist violence.

GOP Sen. Lindsey Graham of South Carolina, often one of Trump's fiercest defenders in Congress, at the time said the president's words were "dividing Americans, not healing them."

"President Trump took a step backward by again suggesting there is moral equivalency between the white supremacist, neo-Nazis and KKK members," Graham added.

America's global image has declined significantly under Trump, who has repeatedly insulted key US allies while cozying up to dictators.

As Insider reported in March:

• Confidence in US leadership declined significantly between 2016 and 2017, according to a new report from the Institute for Economics and Peace (IEP).
• The report found people on average now have more confidence in Chinese leadership than in US leadership.
• Steve Killelea, the founder and executive chairman of IEP, told Insider that global confidence in US leadership experienced a "precipitous drop" after Trump's election.
• Killelea pointed to the "poor press" Trump has received internationally, while noting that global confidence in the US was much higher under former President Barack Obama.
• Global confidence in US leadership fell 11.2 percentage points from 2016 to 2017, according to the report.

The president's tendency to push important allies away and isolate the US, including by pulling out of landmark international agreements like the Paris climate accord, has had a palpable impact.

According to a recent YouGov survey reported by Deutches Welles, for example, found 41% of Germans view Trump as more dangerous than North Korean leader Kim Jong-un, Russian President Vladimir Putin, Chinese President Xi Jinping, and Iran's Supreme Leader Ayatollah Ali Khamenei.

Trump in 2016 campaigned on reducing undocumented immigration, pledging to take a hardline approach.

He made good on that promise when coming into office, but has been accused of human rights abuses and violating international law by the UN.

The Trump administration's "zero tolerance" policy on illegal border crossings led to the separations of at least 5,500 families and saw children placed in cages.

The president of the American Academy of Pediatrics at the time described the practice as "nothing less than government-sanctioned child abuse."

After widespread backlash, Trump issued an executive order in June 2018 to halt the family separations, and a federal judge ordered the Trump administration to reunite all those it had separated. But the fallout from the separations is ongoing.

Trump has falsely blamed his predecessor, former President Barack Obama, for the policy that saw thousands of children separated from their parents.

Meanwhile, at least six migrant children have died in US custody since September 2018, leading to widespread condemnation of conditions in detention facilities.

The UN human rights chief, Michelle Bachelet, in July said she was "shocked" by the US government's treatment of migrant children and the conditions they faced in detention facilities after crossing the border from Mexico.

"As a pediatrician, but also as a mother and a former head of state, I am deeply shocked that children are forced to sleep on the floor in overcrowded facilities, without access to adequate health care or food, and with poor sanitation conditions," Bachelet, the former president of Chile, stated.

Trump's decision to unilaterally withdraw the US from the 2015 nuclear deal in May 2018 has induced chaos throughout the Middle East.

It remains one of Trump's most unpopular decisions in the global arena, and has been condemned by top US allies who were also signatories to the deal.

The president has failed to thwart Iran's aggressive behavior in the region via a maximum pressure campaign, which is meant to squeeze Tehran into negotiating a more stringent version of the pact.

After a series of incidents in the Persian Gulf region over the summer, tensions between Washington and Tehran reached historic heights and sparked fears of war.

At the same time, Iran has begun to take steps away from the crumbling 2015 nuclear deal, which was designed to prevent it from obtaining a nuclear weapon. Meanwhile, on the final day of 2019, the US embassy in Baghdad was attacked by supporters of an Iran-backed military in Iraq.

Trump's decision to pull US troops out of northern Syria in October is also among his most disastrous foreign policy moves. In doing so, Trump effectively abandoned US-allied Kurdish forces who bore the brunt of the US-led campaign against ISIS to a Turkish military invasion.

The withdrawal induced a humanitarian crisis and created a security vacuum that Russia, Iran, and Syrian President Bashar al-Assad, an accused war criminal, all benefited from.

The late Sen. John McCain's iconic "thumbs down" vote denied Trump a full Congressional repeal (even a "skinny repeal") of former President Barack Obama's signature health care law.

However, Trump has had success in dismantling parts of the law. His tax bill included a roll back of the tax penalty for those who did not enroll in health care, and the Trump administration has had some success in the courts regarding the individual mandate.

Earlier in December, a federal appeals court struck down a core part of the law — the individual mandate. It did not overturn the entire law, sending it back to a lower court, and leaving the fate of Obamacare uncertain as an election year focused on health care intensifies.

What Trump has not done in his first three years is offer a replacement for the Affordable Care Act. As the Associated Press points out, as a candidate Trump promised "insurance for everybody" and a more immediate replacement to the nearly decade-old ACA.

The president said he would introduce a "phenomenal health care plan," during an interview with ABC News in June.

Trump was impeached in the House of Representatives on December 18.

The House approved two articles of impeachment against Trump, one for abuse of power over his dealings with Ukraine and one for obstruction of Congress over his efforts to stonewall the impeachment inquiry.

Trump urged Ukraine to launch investigations into his political rivals as he simultaneously withheld about $400 million in congressionally-approved military aid from the country, which is fighting an ongoing war against pro-Russian separatists.

The president is likely to be acquitted in a Senate trial, but will still go down as just the third president in US history to be impeached.