Over the last year, the Obama administration has aggressively pushed a $433-million plan to buy an experimental smallpox drug, despite uncertainty over whether it is needed or will work. Senior officials have taken unusual steps to secure the contract for New York-based Siga Technologies Inc., whose controlling shareholder is billionaire Ronald O. Perelman, one of the world's richest men. Siga ... was the only company asked to submit a proposal. The contract calls for Siga to deliver 1.7 million doses of the drug for the nation's biodefense stockpile. The price of approximately $255 per dose is well above what the government's specialists had earlier said was reasonable. Once feared for its grotesque pustules and 30% death rate, smallpox was eradicated worldwide as of 1978 and is known to exist only in the locked freezers of a Russian scientific institute and the U.S. government. There is no credible evidence that any other country or a terrorist group possesses smallpox. If there were an attack, the government could draw on $1 billion worth of smallpox vaccine it already owns to inoculate the entire U.S. population and quickly treat people exposed to the virus. The vaccine, which costs the government $3 per dose, can reliably prevent death when given within four days of exposure.