Leftist refers to someone on the far left side of the political spectrum, perhaps initially a moderate but then more liberal, such as a progressive, socialist, communist or a particularly liberal member of the American Democratic Party. A leftist supports collectivism, more government control of the economy, direct government control over social policy, including Federal control over education at all levels, lower military spending, censorship of religion, a living constitution, same sex marriages, a more unisex society, globalism, transnationalism, taxpayer-funded abortion, and censorship of Christianity in public places.
Anarchist thinker Michael Bakunin critiqued prominent leftist theoritician Karl Marx in 1873 with these words,
- "..if the proletariat is to be the ruling class, over whom is it to rule? ...the peasant "rabble" who, as it is known, does not enjoy the sympathy of the Marxists who consider it to represent a lower level of culture, will probably be ruled by the factory proletariat of the cities. Or, if this problem is to be approached nationalistically, the Slavs will be placed in the same subordinate relationship to the victorious German proletariat in which the latter now stands to the German bourgeoisie." 
In the United States men such as Eugene Debs, Maurice Hilquit and Norman Thomas believed they could, by a gradual series of alterations in the structure of society, create a truly democratic world in which all people would enjoy not merely freedom, but prosperity. They believed this could not be achieved under the system of private property and profit. They advocated a gradual acquisition by the State of all the great utilities, transportation, communication, and basic industries such as coal, oil, and steel.
The dream of a cooperative commonwealth in which all would share equally in the prosperity created by an economic system owned by the people was the vision of Socialists. This in theory would end poverty, ignorance and crises. The idea was to nationalize banks, railroads, all means of transport, mines, and a few basic industries, but leave some factories, stores, farms, entertainment industries, etc., in the hands of private owners. The government would assume responsibility for making the economy work, for the wellbeing of all the citizens, their protection from the hazards of life, poverty, sickness, and old age. To make the whole economy work continuously without occasional boom-bust cycles, the government would create economic planning boards which would continuously study and observe the functioning of the economic system and make plans covering production, prices, distribution, financing, profits, wages, hours, etc. Thus there would be Planned Capitalism, with the State responsible for the planning and for ensuring the carrying out of its plans through great government bureaus armed with the necessary powers to enforce compliance.
In the 1920s Mussolini had adopted the Planned Capitalist State. And he gave it the name "fascism". Hitler adopted the same idea and called it National Socialism. Mussolini and Hitler both realized that a system which imposes a vast complex of decrees upon a people while subjecting them to confiscatory taxes to support the immense activities of the government cannot be operated except by an absolute government that has the power to enforce compliance. Prior to World War II, this type of system had spread all over Europe. For nearly 70 years all the countries in Europe, with Germany in the lead, had been experimenting with the idea of the welfare state, the State which attempts to provide its people with jobs and protection from all the hazards of life.
This system is the direct opposite of classical liberalism. It is the negation of the classical liberal philosophy which for decades has been fighting to emancipate the people from the tyranny of the all powerful State. During the New Deal this doctrine became known in America as "liberalism". Liberals did not admit that it implied the restoration to the State those very powers which had been stripped from the State as the means of giving people freedom. They called it the Planned Economy. But it was and is fascism by whatever name it is known. Incrementally the government must be made stronger, and the rights of the citizens reduced.
Modern leftists in the United States have come under increasing criticism as advocates of thought control.  Author David Limbaugh cites, "Consider the subjects of evolution, global warming, special rights for homosexuals and abstinence education. Consider efforts of the left to silence conservative talk radio. Consider the mainstream media's arrogant denial of its transparent liberal bias, pronouncing itself to be above politics and inherently objective and its critics somehow skewed....Consider the leftist refrain that red state conservatives do not merely possess a different world view, but are not part of the 'reality-based community.'"
During the French Reign of Terror of the early Enlightenment, the left attempted a dechristianization movement to replace the "reactionary" worship of God and replace it with the worship of national patriotism, or the Patrie. Many churches were closed and converted into Temples of Reason.  The left even formed a new calendar secularizing Christian holidays. This calendar was short lived though and was never accepted in the rural, more religious parts of France.
- V. I. Lenin, "Left-Wing" Communism, An Infantile Disorder (1920) V. I. Lenin, Selected Works, English edition, Foreign Languages Publishing House, Moscow, 1952, Vol. II, Part 2.
- John J. Ray (M.A.; Ph.D.), THE MOTIVATIONS OF POLITICAL LEFTISTS