支配権を握る。の英語

to hold sovereign power―wield the sceptre

to assume the power―wield the power

rise to power

to wield political power―assume the reins of government―take the reins of government

to hold real power

hold the balance of power

to assume the hegemony―gain the ascendancy―maintain one's supremacy

to exercise sovereign power

holding the reins of government

any means of control

be in government

to assume the hegemony―gain the ascendancy―maintain one's supremacy

take the helm of state (affairs)

He holds real power

to assume the reins of government

to wield military power

to rule with authority

the effective ruler

to be able to hold power

Grab power

to have the power of the sword―have the right of war and peace

take control of…

to command a foreign market

a rise to power

to hold the destinies of the land in one's hands

despotic rulers

to wrest control from a person

to hold the supreme power of the state―wield the sceptre―sway the sceptre

He holds the destinies of the land （in his hands）.

assume [hold, take over] the reins of government