Thank you for the opportunity to help you with your question!
Although conservatism has much older roots in American history, the modern movement began to gel in the mid–1930s when intellectuals and politicians collaborated with businessmen to oppose the liberalism led by President Franklin D. Roosevelt.
After World War II conservatism gained strength from new think tanks and writers who developed an intellectual rationale for conservatism
The three reasons for the rise of conservatism towards the later part of 20th century can be –
1. Vietnam war made people disillusioned with aggressive economic policies.
2. Richard Nixon’s victory to presidential election in 1968. Republican came in power and promoted conservatism
3. In the 1980s President Ronald Reagan solidified conservative Republican strength with tax cuts, greatly increased defence spending, deregulation, a policy of rolling back communism.
4. Conservative think tanks 1990–97 mobilize to challenge the legitimacy of global warming as a social problem. They challenge the scientific evidence, argue that global warming will have benefits, and warn that proposed solutions would do more harm than good.
Overall, rise of conservatism helped right wing people to gain control of the Republican Party. Conservatives generally distrust the United Nations (UN) and Europe and, apart from the libertarian wing, favor a strong military and give enthusiastic support to Israel.
This is a long question, but I have tried my best considering 20 minutes time and $1 price tag (easy question)
Please let me know if you need any clarification. I'm always happy to answer your questions. Kindly best this answer if it has helped you.
Content will be erased after question is completed.