Just repeating it again and again doesn't make it true. Again, we have emprical results of tort reform in plain view in Texas and the results are mixed at best. Granted, premium growth did slow or drop in Texas in parts of the mid 2000's- but they also did so nationwide as the spike in premiums across all types of insurance in the early 2000's was due to a pretty well documented spike in the insurance underwriting cycle, in which insurers raised premiums to account for investment losses after the dot.com bust.
Here's a 2005 study on estimated savings if all states w/o malpractice caps enacted one of $250,000 on noneconomic damages. ($1.4 billion) http://www.rwjf.org/reports/grr/050298.htm The study didn't offer potential consequences of instituting those caps, but we can't assume that there wouldn't be any or that it would justify saving 1.4 billion/year over it. Food for thought on the malpractice reform claim.
The thing is, tort reform has not reduced malpractice insurance premiums in Texas since we capped awards. What makes you think that would be different on a national scale?