[tbeatty]

Today, after a half-century of research and billions of dollars of investment, the SDI program is generally considered a failure, and there is still no realistic means of defense against a nuclear missile attack.

I think I would describe it as "in development." But then again, I'm not from the ultra-left wing PBS.

[dighton]

... the SDI program is generally considered a failure ...

Typical dishonest use of the passive voice. Such writers are generally considered fit for flogging.

[manx]

If SDI was a failure why have they already shot down several missiles and are now building a laser to fit in the nose of a large plane.

The future is in laser technology and many people are going to be eating thier words before long.