Aside from that you haven't thought about the implications of an ID system in the current political climate. Some advocates even state their real goals openly.
I don't think you are very liberal here for that matter. It is just a single issue, but it strongly correlates with positions around this particular topic.
Here are my leftist views: No one should have more than $10 million of wealth. Everyone should have a place to live, food, and healthcare. Healthcare should be free at the point of usage. The U.S. should stop funding Israel. Higher education should be free. Churches should pay tax on the property they own. Donations to charity should not be tax deductible. Public transportation should be heavily subsidized and greatly expanded. The DOD and CIA and NSA should be greatly reduced in size and scope. Elections should be publicly funded so that each candidate gets an equal amount of funding. Abortion should be legalized everywhere. Homeschooling should be outlawed.