Ask HN: 2 karma minimum to lock out spam bots

I just flagged two submissions that were blatant spam, both submitted by accounts created two seconds before the post.

Wouldn't a 2 point karma minimum to url submission and voting fix a lot of spam posts? For legitimate users it's pretty easy to get one upvote on a comment and as a nice bonus it would raise the chance that the user has a basic grasp of community values.

For spam bots OTOH it's impossible to submit links before they get one upvote and it's impossible to upvote themselves before they get one upvote. I think that it effectively locks them out.