Monopoly is nearly always seen as something undesirable. Courts have wrestled with monopoly for ages, sometimes defining it as: "the power to control prices and exclude competition," "restraining trade," or "unfair and anti-competitive behavior." Should monopolistic practices be condemned and outlawed?

Answer: No

As stated in the question itself monopolies are "nearly always" seen as something undesirable. In most markets a monopoly would be undesirable such as the market for dairy but in some markets monopolies must not only be allowed but in fact created by the government. An example is the pharmaceutical industry. With billions in research costs, a monopoly given through patents is the only way for the research to be done. Thus, monopolies should not be banned but regulated in certain cases. Other monopolies exist because of an economy of scale which puts a ceiling on the the price they can charge and can result in a better outcome than a competitive industry.