Over the last ten year or so, the employment protections afforded to disabled Americans have shrunk as a result of federal-court decisions (notably the Supreme Court's decisions in Sutton v. United Airlines, 527 U.S. 471 (1999) and Albertson's, Inc. v. Kirkingburg, 527 U.S. 555, 565 (1999) focusing on who is a "qualified individual with a disability" and what is an "impairment." The gist of the rulings is that a person is not disabled for purposes of the ADA if the person can eliminate substantial limitations on major life activities by mitigating measures such as drugs, devices, and coping mechanisms. The National Council on Disability has a nice summary of the role of mitigating measures in ADA cases.
The House of Representatives recently passed a bill (HR 3195) to revamp some of the statutory language of the ADA in order to undo what the Court has done with Sutton and Kirkingburg. Both major-party presidential candidates have indicated their support (scroll down to "Broader scope for disabilities act") for such legislation, so maybe it has a chance of enactment.
Hey, didja know Michelle Obama's dad has MS? It's too bad that the causes of disabled Americans are fragmented into individual "disease lobbies," but wouldn't it be great to have someone in the White House who knew first-hand what it's like to live with MS?