Britain's Golden Age

Britain's Golden Age was the term given to the era under which Harriet Jones served as Prime Minister of Britain. Though the name suggests a peaceful era for Britain, it was actually a period of much conflict. The term was first used by the Ninth Doctor after Jones took charge of the aftermath of a world crisis, following a hostile takeover from the Slitheen family. The Doctor had high hopes for Harriet's term, but when he discovered a dark side to her rule in his tenth incarnation, he acted swiftly to get her removed from power, aborting the era before it came to pass.

History
During Harriet Jones's rule, Britain became more involved in the defense against alien attacks due to Jones's views and fears towards the damage they could inflict on human society, following its previous altercation with the Slitheen. (TV: Aliens of London/World War Three)

Britain's Golden Age was marked by several initiatives to keep the public safe from these potential attacks. There were also attempts to outreach to alien life to see if there were aliens willing to befriend Earth, which would dispel the fears humans had towards extraterrestrials. When the first significant outreach was met with an act of violence and invasion from another alien race, the Sycorax, Harriet submitted to her belief that Earth had to be defended from all aliens, resorting to deadly measures to keep it out of their hands, ordering Torchwood One to open fire on the Sycorax, killing the entire fleet. The Doctor responded with extreme fury, calling it a genocide. Disgusted, he chose to stop her rule immediately by instilling the notion that she was tired into her aide, Alex Klein. This trickled down to affect her standing with the public and various other authority figures, which increased her paranoia and led them to think she was growing ill. Eventually, she was voted out of her position by the House of Commons. Had the Doctor not interceded with the course of history, Harriet would've carried out three terms as Prime Minister. The so-called "golden age" was nothing more than a positive forethought compared to what Jones was actually doing to protect the planet. The Doctor chose to stop her legacy from being defined in order to keep Britain's views towards alien life from becoming aggressive, which effectively erased the notion of Jones's rule becoming a "golden age" from history. (TV: The Christmas Invasion)

Precursor
In 2006, the Slitheen family had infiltrated the Earth and terrorised the public by staging a hoax alien attack on London, crashing one of their spacecraft into Big Ben with a genetically-altered pig posed as its pilot. Taking advantage of the citizens' fears, they disguised themselves as several strategic military and political powers, killing off the original humans to take their skins as body suits. One of these was the former Prime Minister of Britain, allowing the Slitheen to puppeteer the government through one of their own disguised as an Acting Prime Minster, Jocrassa Fel-Fotch Passameer-Day Slitheen. (TV: Aliens of London) The Slitheen family used scare tactics to goad the United Nations into giving them the launch codes to their nuclear warheads, promising to fire them at an enemy fleet that had gathered in space above the planet. The Slitheen would ensure these warheads would instead hit innocent nations and trigger World War III, leading to the complete annihilation of Earth. The Slitheen would sell off the radioactive remains for profit. (TV: World War Three)

The Doctor, his companion Rose Tyler, and Harriet Jones, an M.P. for Flydale North who had become caught in the Slitheen conflict while seeking acknowledgment for her skills, were trapped at 10 Downing Street in the armored Cabinet Room as the Slitheen prepared to destroy the planet. In a last resort to stop the Slitheen, the Doctor contacted Mickey Smith through Rose's superphone and guided him through the process of logging into the Royal Navy's systems to take control of a Harpoon missile from the HMS Taurean, a Trafalgar class submarine off the coast of Plymouth, which he aimed at 10 Downing Street. The missile obliterated the residence, killing all Slitheen inside, save for Blon Fel-Fotch Passameer-Day Slitheen, who escaped. The Doctor, Rose, and Harriet survived the missile strike inside the heavily armored Cabinet Room, the only part of the building to withstand the attack. (TV: World War Three)

Rise to power
After the Slitheen crisis had come to an end, Britian was in a state of turmoil. The Doctor had been impressed by Harriet Jones's initiative during the crisis. When she wondered how the country would rebuild from the Slitheen's attacks, he suggested to her that she could become Prime Minister. Harriet quickly took charge of the press and emergency services, announcing proudly that the crisis has passed: that "mankind stands tall, proud and undefeated". Up until now, the Doctor had believed Harriet's name was familiar. He remembered that Harriet would become future Prime Minister, elected for three successive terms, and the architect of Britain's Golden Age. (TV: World War Three) However, the Doctor only knew about her exploits from her positive public image alone. When he discovered the truth behind her term, he cut it short by force.

An age short-lived
Harriet Jones was indeed elected as the new Prime Minister later in 2006. She served her term up into Christmas of that year. During this time, she got involved with UNIT to further her attempts to keep Earth sound from alien attack. This pursuit to defend the planet eventually led her to associate with the Torchwood Institute, specifically Torchwood One, which began to serve under her command for the welfare of Britain concerning alien threats, which proved to be an unethical relationship, though kept secret from the public. When Christmastime arrived, Jones held a press conference about the launching of the space prove Guinevere One with project director Daniel Llewellyn, planned to land on Mars. However, it was captured by an alien spacecraft that identified themselves as the Sycorax, who sought to conquer the planet. Jones spoke to the citizens of Britain during the invasion of the Sycorax in an emergency broadcast, assuring them they would be kept safe. (TV: The Christmas Invasion)

Harriet chose to confront the Sycorax directly in an attempt to reason with them, along with her aide, Alex Klein. They were joined by Llewellyn and Major Richard Blake, who were both killed when they challenged the authority of the Sycorax leader, Fadros Pallujikaa. Harriet hoped the Doctor might turn up to help her but instead, Rose and Mickey arrived in his TARDIS. The Doctor had recently regenerated following the Battle of the Game Station, and had gone into a deep sleep to recover from the metamorphosis into his tenth incarnation, now onboard the TARDIS in a coma after a premature awakening worsened his condition. After a shaky standoff with the Sycorax, Jones feared that the safety of the planet's people, a third of which had been placed under blood control, was in dire jeopardy. The Doctor awoke from his regenerative coma and defeated Fadros Pallujikaa in mortal combat. This prompted the Sycorax to flee the planet, knowing it was protected. (TV: The Christmas Invasion)

Downfall
The Doctor commended Harriet once again for handling a crisis with finesse. However, Harriet Jones was not amused at the prospect of many more alien races like the Sycorax lurking in outer space. This thought caused her to reluctantly allow Torchwood One to open fire on the Sycorax's spacecraft with a confiscated alien weapon, which destroyed the ship, along with the Sycorax onboard. Immediately, the Doctor's views of Harriet were shattered, and he confronted her tempestuously for what she had just done. Harriet had indirectly caused genocide, angering him greatly. Harriet defended her reasons for killing off the Sycorax as a necessary sacrifice to ensure Earth would not come under attack by more hostile alien species, expressing a desire to not only guard Britain, but the whole world from any further intrusion. Furious at Jones for abusing her power, the Doctor threatened to bring down her government with one word, which Jones rebuffed, thinking it was beyond his ability. The Doctor changed his statement accordingly, saying he could bring her down with six words. Harriet challenged him a second time, a mistake that cost her the remainder of her projected term. The Doctor walked up to her aide, Alex, and whispered in his ear, "Don't you think she looks tired?" Alex became visibly unnerved. (TV: The Christmas Invasion)

End of the Golden Age
Harriet's overconfidence gave way to fear when she saw Alex's reaction to the Doctor's question. She panicked and asked what he had said to him, but he did not respond. These words started a ripple effect as they were passed down from Alex to several other government authorities, while Harriet grew progressively more paranoid at the idea she would be removed from power, becoming less capable of hiding it with each passing day. As Harriet began to fall apart from the paranoia, she was suspected to be of ill health, prompting the powers that be to intervene. Harriet was evicted from her rule as Prime Minister of Britain when the House of Commons ruled in favor of a vote of no confidence, bringing a premature end to her term as a consequence for her behavior. (TV: The Christmas Invasion)

Aftermath
Harriet Jones was soon replaced as Britain's Prime Minister by an up and coming figure in politics, Harold Saxon. Unfortunately, Harold Saxon was an identity concocted by the Doctor's long-time nemesis,, which he used to subject the planet to the Year That Never Was, a rule undone by the Doctor, Martha Jones, her family, Captain Jack Harkness, and the Master's own wife, Lucy Saxon, among many others. (TV: The Sound of Drums/Last of the Time Lords)

Harriet did not reclaim the political stature or greatness that she once had. However, she had become humbled by the loss of authoritative power and sought to amend her soured relationship with the Doctor. Harriet finally redeemed herself in the Dalek invasion of Earth. She worked alongside Torchwood Three, a morally straighter branch of Torchwood headed by Captain Jack Harkness, along with several key allies of the Doctor, who collectively united as a group deemed the Children of Time to contact the Doctor in their time of need. Unfortunately, in order for the group to do so, Harriet allowed her location to be exposed to the Daleks. The Daleks quickly tracked Jones down and cornered her, exterminating the former Prime Minister. (TV: The Stolen Earth) Harriet's final act absolved her previous wrongdoings, but proved that the consequences of her rule were much greater than she could have foreseen.