Determining success as a Writer

I fancy myself to be a lot of things, and of the many things that I’ve taken up as hobbies, Writing is one that I feel has measurable milestones of success, instead of just levels of proficiency.
I knew I was good at other things when someone unrelated to me told me that I was good at it.  Or rather, if you’re good at something, you show people, so that your abilities are known. But,  I’m not sure I’m successful at writing, even after others have told me that I was ‘good’, because I was lead to believe that ‘writers’ have published works.
This blog is, arguably, one of the most intellectual things that I do. With it, I cover a variety of serious social issues. But still, Blogging seems too flexible to be real Journalism since  it’s only a step away from micro-blogging, like Tumblr.

Blogs are a relatively new invention. They did not really exist before the wide spread availability of the internet. The World Wide Web as we know it was invented in the 90s. It makes sense that literature purists would deny the legitimacy of digital self-publication platforms. Fifty years ago, all forms of writing had to be distributed to the public in paper format. There was a certain tactile significance to printed paper that we grew accustomed to, awarding higher value to a something that we can touch. A ritual we still use today for special situations, like ceremonies, diplomas, and certificates.  As if being able to touch it makes it more valid.
If I published my blog into a physical paper book, would I be a blogger? or a writer?

The internet is so new that self-publication platforms fall into a legal grey area. In a court case for defamation/libel, a court found that bloggers are journalists in a situation where a blogger investigated and wrote negatively about a corrupt finance group. Apparently, 1st amendment freedom of speech didn’t fully extend to writing whatever you’d like in a blog of personal insights. Because, in that court,  bloggers were deemed legally equivalent to journalists. This court took a self-published blog as seriously as it would a traditional printed journal. Defamation is deliberate false slander, and while most of the blog was opinion, some of it wasn’t, and the blogger lost the case.

-Novelist, author, journalist, columnist, play writer, ghost writer, blogger, lyricist. Are these words synonymous? The differences between them exist, however slight it seems, it’s significant enough to cause a new term for that type of writing to exist. The English language is tricky that way.  -So what’s a step-up from Blogging? Is there a platform that appears more professional and less hobbyist?
The criteria for being a musician is to make music. Why am I not confident that writing a blog makes me a writer? I’ve found ways to demonstrate my other talents. Why is it so much more difficult to showcase my Writing in a way that will establish its success?