A tyrant will always find a pretext for his tyranny meaning

One common characteristic of all tyrants is that they always find a reason to continue ruling.

Explanation:

Tyrannies always find a reason for not giving the power to other rulers, their pretext is that no one can do the job as well as they do.

Tyrannies always blame foreign countries or parts of their own societies for their problems.

In the case of Nazi Germany, Hitler blamed the Jews for Germany's economic problems, once he had German Jews in ruin, he continued with the Jews in other countries, this ended in 2nd World War.

In Cuba, Castro blamed the United States for his poor economy, although he could never solve Cuba's problems, he keft power till the end.