This speech was given about three weeks after the Iranian hostage crisis in which Iranian Islamists took fifty Americans, working at the U.S. embassy in Tehran, hostage in November of 1979. This was Thatcher's first visit to Washington after becoming Prime Minister of the United Kingdom, about three months earlier. She ran on a platform of completely changing Britain's Democratic Socialist ways and moving past a welfare state that tried take complete care of all citizens.
Prime Minister Thatcher wanted to create an opportunity and entrepreneurial society where Brits would be able to take care of themselves. She did not want the British government to be running major sectors of the economy. She wanted energy and aviation to be run by the private sector. She was certainly not a socialist nor even a liberal, conservative, or even a libertarian in the American sense. By American standards, the best way to describe her would be as an economic progressive.
Prime Minster Thatcher didn't want to eliminate the welfare state in Britain but she didn't want the welfare state to take care of people who could take care of themselves if they just had a good job. She thought that the government should not try to run people's lives and that Brits should be permitted to manage their own economic affairs. The results, in terms of where Britain was economically when she took over in 1979 and when she left office in 1989, show that she was very successful.