Government engineered false-flag terrorism is a historically established fact. For centuries, political and financial elites have been sinking ships, setting buildings on fire, assassinating diplomats, overthrowing elected leaders, and blowing people up, then blaming these disasters on convenient scapegoats so that they can induce fear in the public and transfer more power to themselves.
Skeptics might argue whether certain calamities have been proven beyond a reasonable doubt to be false-flag events, but no one can argue that such tactics have not been used by the establishment in the past. Governments have openly admitted to creating bloody and catalyzing tragedies under false pretenses, like Operation Gladio, a false-flag program in Europe supported by European and American covert agencies which lasted decades, from the 1950's to the 1990's.