It's based on insidious (slow, subtle, gradual harm) and assiduous (constant application & attention to detail until task is finished), combined with the new Sith philosophy — the rule of two — to sit, wait and work in secret at the whole plan to destroy the Jedi (as was the Sith’s original goal).
His character believed he was the Sithari — the chosen one of the Sith, the culmination of 1000 years of Sith evolution. He learned through his prolonged study of Sith history to renew the way the Sith operated.
He cultivated a small but powerful Sith Order to use against the Jedi and entered politics to work in secret (but in plain view as a Senator) to infiltrate the Republic. The discrediting of the Jedi was his whole plot, combined with Order 66 so he was only left with a small number of Jedi to deal with in his rise to power, which he totally orchestrated & manipulated through controlling the war as the villain and the hero by keeping battles even to prolong the war and exhaust the Jedi.
Also so much study of the Dark Side made him pure evil as he was able to train with his master for decades to learn all he could to prepare himself for his plan to become Emperor by gaining power through the illustrious career of starting and controlling outcomes of war, slowly guiding events to align with his plan until he could gain emergency power to execute Order 66. The phantom menace was his beginning as the new improved Sith & mastermind of the Republic.
