opportunism

noun

1. (countable, uncountable)The practice of taking advantage of any situations or people to achieve an end, often with no regard for principles or consequences.
2. (Marxism, countable, uncountable)The political line of Communist Party members who zealously support the Party, but whose trait is that they yield to the mood of the moment, they are unable to resist what is fashionable, leading to the sacrifice of the permanent and essential interests of the Party to the momentary and minor interests.