The phrase "activist could have" is correct and usable in written English.
It can be used to discuss hypothetical situations or possibilities regarding the actions or decisions of an activist.
Example: "The activist could have influenced public opinion if they had more media coverage."
Alternatives: "activist might have" or "activist was able to".
The activists could have tried something similar.
The letter went on to suggest that the activists could have chosen to protest against the Syrian or the Iranian governments or Hamas rule in Gaza.
The G2 or Second Generation theory, whereby children of Holocaust survivors are often socially conscious activists, could have had something to do with it, however it was never discussed.
Had the health care bill failed, the Tea Partiers and other right wing activists could have had a substantial victory to their credit.
In a less febrile atmosphere, the activists could have used this sort of hype and it would have been dismissed as just that – hype.
In a gesture that local communities and activists could have only dreamed of a few years ago, Widodo then took part in damming up a canal, used by illegal loggers to drain away water and prepare the rainforest and peatland for burning.
Under the Texas 1995 food-libel law, Ms. Winfrey and the anti-meat activist, Howard Lyman, could have been held liable if the jury had decided that the two had knowingly made false statements about the beef supply or the risk of mad cow disease.
The activist cause could have been strengthened and validated by putting aside their need to be right and speaking in unison for something they both agreed with anyway.
The group I helped found in FREE FOR ALL!, Video the Vote, saw its ranks flourish going into the 2008 election, and the concerted efforts of election protection activists nationwide could have arguably made the difference in any number of states.
