What events in the 1980s motivated Christian conservatives?

The election of Ronald Reagan as President in 1980 was due in no small part to the tireless campaigning and support of evangelical Christians. By this time, evangelicals had become a major force within the Republican Party, using their growing power and influence to promote their conservative agenda. On the domestic front, this revolved largely around a pushback against social liberalism. Conservative Christians were deeply hostile towards abortion, for example, and saw its increased availability in the wake of Roe v. Wade as a fundamental challenge to traditional values.
In relation to foreign policy, evangelicals in the Republican Party looked at the growing assertiveness of the officially atheist Soviet Union as an existential threat to "Christian America"—one that needed to be met with an appropriately aggressive response from the United States and its allies. To such Christian conservatives, the Cold War wasn't just a geopolitical rivalry between two competing ideologies: it was an epic battle of good versus evil, and they were determined that the good side—with which they identified themselves, of course—should ultimately prevail.