Final answer:
Japan, Germany, and the USA are the primary manufacturers of the high-quality steel used in professional shears, with the USA historically becoming the leading steel producer in the early 20th century.
Step-by-step explanation:
The countries primarily responsible for manufacturing the high-quality steel used to make professional shears are Japan, Germany, and the USA. These nations are known for their advanced steelmaking technologies and the production of high-grade steel that is essential in crafting professional shears and other precision instruments.
The rapid growth of the American steel industry in the late 19th and early 20th centuries, where production increased dramatically and the USA became the top steel producer, is a testament to the country's pivotal role in steel manufacturing. This industrial growth made steel more affordable and essential for various industries, such as construction and automotive, contributing significantly to economic development.