Sentence:  He had formed plans not inferior in grandeur and boldness to those of Richelieu, and had carried them into effect with a <WSD>tact</WSD> and wariness worthy of Mazarin. 
Meaning of the word marked with <WSD> tags:  Sensitive mental touch; special skill or faculty; keen perception or discernment; ready power of appreciating and doing what is required by circumstances; the ability to say the right thing. (from early 19th c.)