Inspired by this question: How many of a Typical Sci Fi Army would you need to take a planet?
Let's have a Galactic Empire which spans the galaxy. The Empire is ruled by The Emperor from one central planet. As you guessed, we are in alternate universe where travelling and communicating faster than light is possible without breaking any laws or creating any paradoxes (one big handwave).
All the planets must obey strict Empire rules and pay a pretty high amount of taxes to keep the Empire's military running.
The army keeps everyone from rebelling against the Emperor, because if you do so, the Empire will use sheer amount of power on you, including blowing up your planet.
The "blow the planet" accident happened just once, but everyone knows that The Emperor is going to approve even such a terrible action as blowing you up, or nuking all the ground from the orbit.
Civil ownership of weapons is highly regulated, common citizen will get a maximum blaster. All higher grade of weaponry is restricted to the army, including ship shields and ship weapons.
All production of weapons is highly monitored and anyone producing weapons is painfully punished and this punishment is then broadcasted live in Empire news.
All the population is kept being broadcasted by Empire propaganda, including info how awesome being in the military is. Common military person is held on high standard, therefore military members are happy and consider The Emperor as the second best thing after sliced bread.
You are a member of one of the planets belonging to The Empire. Your planet is on the Galactic outskirts, with a relatively small population of 500 million people.
Thanks to the fact that you are in the "wild waters of the Empire," a fair share (30%) of the planet population are having rebellious nature.
Is there a chance to gain independence without being nuked?
Every single planet of The Empire has a military base and governor loyal to The Emperor (high rank military member, at older age). The communication inside the Empire happens instantly and military ships can travel from one edge of the galaxy to another in a year.
P.S.: No Star Wars reference. I am just bad in coming up with names