Not that you don't have a point: prioritisation is extremely important. But also keep in mind that it's a normal political sleight of hand to keep you occupied with X, while the real goal is Y. For example, someone who wanted to push forward copyright changes, but expects problems could propose a subsidy for burning coal and while people are distracted by that, to push through their copyright changes.
If your elected official only thinks that X is important, then they may be willing to give up Y whenever anyone threatens X -- no matter how serious a threat it is. Holding public officials accountable is very hard work, which is another reason why they can frequently get away with questionable actions and still get re-elected.
I tend to think that directly actionable things are better to focus on. So promoting free and open source software, and ensuring that it becomes the backbone of software development is more effective than discussing copyright issues with your congressman. However after making the issue important to a wide class of people, you can't neglect the political side.
On the other hand, I would never criticise someone for deciding to prioritise a cause like the environment, or government corruption over copyright issues. A single person can only do so much. But if you are motivated by copyright issues, then I wouldn't hold back just because there are other, seemingly more important issues on the table -- because that hesitation will be used against you.