Liferay uses RBAC permission model, which probably won't allow you to achieve this through permissions. This is because it's utterly illogical to deprave a system role from a permission granted to a guest.
Another way of achieving this is to create a public page which contains the Login portlet, let's say the page is called Login (this page and it's portlet should be viewable by guests).
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.