It depends on context. If you have never built a web application, it can be very difficult task grasping what exactly Rails does for you (even it your are experienced in programming languages). For someone who has been building web applications for years, the it may be easier for that person to understand the pain points that Rails solves. Since Rails is domain specific to web development, you're not necessarily learning programming, but really how to apply programming to web development based on the framework's conventions. The bottom line is that you're learning something new. How hard the learning is depends on the foundation you're currently have that you can build upon. Having a foundation in a programming language doesn't necessarily mean that you're poised get up and running quickly with a web framework if you've never done web development.

The art of building web applications today, in itself, is much more complex than it was 10 years ago - mostly due to the every growing selection of tools that make it easier for experienced developers to build web applications. This in turn can make web development seem daunting.

Personally, when I started learning Rails, I had a foundation of working with rudimentary frameworks in other languages. When I discovered Rails, it did quiet a bit of what those other frameworks accomplished and then some. Then it took it further and pushed the envelope (i.e. REST support for urls and routing, more recently including CoffeeScript and the Asset Pipeline).

While there's a ton of learning resources out there for learning Rails, it can be really hard to put them together and figure out what in what order you need to learn new concepts.

That being said, I think The Flatiron School did an excellent job getting together a list of learning resources: http://prework.flatironschool.com/ - Just a heads up that it recommends CodeSchool and Tree house which are subscription services. If you're serious about learning, I'd consider the subscription cost to be a small investment.

The one resource that Flatiron Prework didn't mention is the Rails Tuturial: http://ruby.railstutorial.org/ruby-on-rails-tutorial-book

If you really want to dive into ruby, I'd recommend The Well Ground Rubyist by David Black.