Congress Told FDA Failed Public on Vioxx  WASHINGTON (Reuters) - The U.S. Food and Drug  Administration failed the public in its oversight of Merck   Co  Inc.'s &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=MRK.N target=/stocks/quickinfo/fullquote"&gt;MRK.N&lt;/A&gt; withdrawn painkiller Vioxx and is "incapable of  protecting America" from another dangerous drug, an agency  researcher told Congress on Thursday.