Reagan was not the panacea that Republicans claim. Of his least egregious actions was the fact that he said little of substance in his speeches. Most of his speeches were feel good. "Atta boy" , "RahRah" speeches where he told his base what they wanted to hear (not unlike Trump).

His next egregious actions is his invention of "plausible deniability". His Adminstration surrounded him with a layer of bureacrats that he deferred to as opposed to him understanding the issues and esablishing policy. That way if someting went awry (aka. Iran-Contra Debacle) he could deny any knowledge or complicity. Unfortunately Trump is not that bright. At least Reagan's cabinet selections were generrally competant as opposed to the set ogrifters and incompetants put in position by Trump and his Republicans.

Everybody says that Reagan brought down the Soviet Union. Thats like saying Trump won the election on his own merits (on the contrary, Hillary lost the election by her own arrogance). The Soviet Union overextended themselves and spread themselves out too thin economically. The Soviets were waging war on too many fronts and it broke them. Reagan does deserve credit for keeping the pressure up, but the Soviet Union had already set their own demise into action.

Reagans Administration fostered in the war on education. The results we are seeing today with Trump his supporters war on facts. The concept of alternative facts, fake news, and the denial of Science gots it beginning under Reagan.

The rise and marriage of the Evangelical influence on Republicans and politics began under Reagan. Falwell and his minions inserted themselves into the White House and never left. Witness Falwell's son, the Tea Party, and the Freedom (Fascist) Caucus and their influence on Trump and the social dialog. Ideologs all.

It was under Reagan that trickle down economics was born. It didnt work then, it doesnt work now. The most recent tax cut package is witness to that. Companies are using tax break saving to do stock buy backs and to pay higher dividends to share holders and large executive bonuses (as was predicted). Reagan expanded the national debt, and it took Clinton to balance the budget and get the country back in the black.

This is the short list of Reagan's failinga. There are more.