Even Margaret Thatcher deserves better than to have Meghan McCain quoting her stupidly. Especially since a lot of what @Ocasio2018 proposes, the UK already has.
"The problem with socialism..." quote from Thatcher is not her finest moment. She attacks socialism on capitalist principles ("other people's money").
Conservatives see socialism as "Robin Hood stealing from the rich and giving to the poor." Wealth in this case is finite. Both arguments are false.
One argument is that we can "promote the general welfare" and look after each other. That is voluntary. It's not theft.
McCain worries about her grandchildren growing up in a socialist nation. Consider this: Her grandchildren, who don't exist, likely have more assets (either in trust or set aside in a will, etc) than children who exist right now. That isn't efficient use of resources.
