One who practices or defends interventionism.(noun)
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Use "interventionist" in a sentence
"To keep attention focused on the use of governmental power by economic actors for their ends, the term interventionist power may be used."
"The second one, which I call the interventionist and harmonisation model, is characterised by enormous centralisation of decision-making in Brussels, by far-reaching regulation of human activities, by harmonisation of all kinds of “parameters” of political, economic and social systems, by standardisation and homogenization of human life."
"The very word and category, "interventionist," is still vexed by the older discussion of engaged art."