The quality of being self-assured and assertive.(noun)
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Use "assertiveness" in a sentence
"China's new assertiveness is more than a matter of provocation and petulance."
"Her assertiveness is based on her enormous resources of oil and gas, something that has given Russia an economic renaissance and put her among other global powers as an equal."
"A belated sorry to those I owe, and I'm working on the 'assertiveness' - not the rudeness."