WASHINGTON (AP) -- When presumptive Republican nominee Donald Trump was "pro-choice in every respect," Indiana Gov. Mike Pence compared abortion to the tragedy of the Sept. 11 terrorist attacks.
When Pence opposed providing gay Americans with the protection of anti-discrimination laws, Trump declared that the Equal Employment Opportunity Commission needed to protect gay rights in the workplace.
And when Trump was applauding state lawsuits against big tobacco companies, Pence declared that "smoking doesn't kill."
Over the past two decades, Trump has disagreed with his vice-presidential pick on plenty of political issues, including immigration policy, entitlement programs and trade. On social issues above all, Trump and Pence arrive at the 2016 general election from very different paths.
In writings on his campaign website in 2000, Pence likened America to the Titanic, "steaming away from the safe harbor of our best moral and religious traditions." Trump, at that time, pronounced himself indifferent to such fears.
"Hey, I lived in New York City and Manhattan all my life, OK?" Trump said in a 1999 NBC interview. "So, my views are a little bit different than if I lived in Iowa, perhaps."
Pence, an Evangelical Christian who doesn't drink, has charted a seemingly immovable social hard-line for decades, tracing back to his failed Congressional bids in the late 1980s and early '90s before his time in the U.S. House and term as Indiana governor.
Trump, a mainline Protestant who also doesn't drink, has revamped his positions on gay rights, abortion and other social issues several times over the years, including some that changed regularly during this election cycle.
The fervor of Pence's historical stance on abortion sets him apart from Trump and even some Republican peers.
At a 2002 anti-abortion march in Washington, Pence lamented that more compassion was shown for the victims of Sept. 11 terrorist attacks than for aborted fetuses.
"How many times on national television did we hear people lament the loss of innocent human life?" he asked, suggesting that abortion should also stir "outrage born of violence against noncombatants."
According to a 2010 candidate survey published by Indiana Right to Life, Pence told the advocacy group that he opposed abortion under all circumstances — even when necessary to save the life of the woman giving birth. Pence softened that stance in a 2012 survey— though he still opposed allowing abortions for victims of rape or incest.
In office, Pence has pursued these principles. Along with supporting traditional conservative legislation, Pence also supported unconventional maneuvers, such as a 2011 gambit to defund Planned Parenthood that nearly forced the shutdown of the federal government.
"Well, of course I am," Pence told MSNBC when asked if he favored blocking the entire federal budget in an effort to strip the group of funding.
Pence has been in a position to take more direct action since his 2012 election as Indiana's governor. Adding to what were already some of the most strict abortion laws in the nation, Pence signed a law in March that bars terminating a pregnancy based on a fetus's genetic birth defects and requires aborted or miscarried fetuses to be buried or cremated. The law was blocked last month by a federal judge.
Pence has taken hard lines on social issues for years, opposing abortion and gay rights and promoting a ban on women serving in combat support roles in the military.
While running for Congress in 2000, Pence also called for a ban on gay people serving in the military.
"Congress should oppose any effort to put gay and lesbian relationships on an equal legal status with heterosexual marriage," Pence wrote in his legislative agenda.
He also called for opposition to "any effort to recognize homosexuals as a 'discreet and insular minority' entitled to the protection of anti-discrimination laws similar to those extended to women and ethnic minorities."
In addition to his views on social issues, Pence has called climate change "a myth" and contended that smoking cigarettes — while certainly unhealthy — isn't lethal.
Writing in articles posted on his old congressional campaign website from 2000, Pence decried government interference in the lives of smokers.
"Time for a quick reality check. Despite the hysteria from the political class and the media, smoking doesn't kill," Pence wrote. Though he still encouraged people to quit for their health, Pence pronounced the greater threat to be a government "big enough to go after you."