abuse of 'at will employment' clause

The 'employment at will' clause is being abused by the employers these days. I am an engineer. In my last job, my employer wrote explicitly the 'employment at will' clause in the offer letter. After few months, my boss told me that the project will stop for at least 4-5 months and they have to 'let me go'. They didn't do any formal exit process, didn't give me any compensation or severance, didn't pay for my accrued vacation, didn't give any discharge letter, just wrote me a check for the last days I worked. In my present job also, my employer wrote explicitly on my offer letter that my job can be terminated for any reason or no reason. 4-5 weeks after started, they have started giving me hints about probable termination. As there is no reason that I can see which might have caused this, I see that they are just misusing the 'at will clause' of the offer letter. Since they write the offer letter this way, there is not much that I can do when I accept the offer. Also I feel it very distressful as I can't do anything here. As an employee where exactly I stand? Is there anything which protects employees from all these abuse? Is there anything in this country which works in a fair (!!!) way?