Anyone not hopelessly naïve or blinded by ideology will recognize that capitalism has serious potential problems. The Robber Barons of the late 19th century and the excesses of Social Darwinism are examples of dangers. There is a need for reasonable governmental regulation to prevent unfair business practices and to protect workers and consumers.
Unfortunately, regulation has its own dangers as regulators assume more and more control (for the good of all naturally, the regulators know best how things ought to be run after all). Too much regulation becomes crippling, lack of regulation opens the door for the unscrupulous to exploit everyone else.
There is also a need for what has been termed a social safety net to provide for people who either temporarily or permanent cannot provide for themselves. Unfortunately, some will always try to game such a system and claim aid that they don't really need.
One area that capitalistic and market driven economics does well is provide incentives for people to work and be productive. If they work well they can receive economic rewards for their success. (One of the reasons for reasonable regulation is to protect against the strong who would rig the system to rob those who work of the fruits of their labor.) If one does not work well, they receive less.
Socialism, as it has demonstrated regularly where it has been tried, usually ends up being economically unsuccessful for most of the population, rife with corruption that siphon off what wealth it creates, and results with oppressive governmental control of the lives of its people. It is perhaps significant that border controls for the US are chiefly concerned with regulating who can enter the US. The Berlin Wall was not constructed to keep West Berliners and West Germans from flooding into the workers paradise of East Germany.
For society to work well and provide for its people there is a need for social welfare programs and regulations of business to help those less able to provide for themselves and curb the greed of the unscrupulous. There is also a need to incentivize productive work. Pure socialism, "from everyone according to their ability and to everyone according to their needs," sounds ideal, and maybe would work for ideal people. But if society is to provide for the needs of people there is need for hard work, often harder than people might do without incentives. Pure socialism depends on people being completely altruistic, which by nature people are not, or forcing altruism - working for the common good rather than one's own - on people. It is the latter that usually results in repression as the government forces people to work for what the government has decided is the common good. It also breeds centralized control of everything. That might work if the governmental managers actually did know everything. But that rarely works well in the long run.
The alternatives are not pure socialism or pure capitalism, but a system that combines some of the best features of both. It is striking the balance that is difficult. Until I learn more about what Bernie Sanders and his comrades mean by Democratic Socialism, I don't trust it.
