Two problems that have dogged laser weapon development for some time are weather conditions and the target itself.

BBC: Anti-aircraft laser unveiled at Farnborough Airshow

Most of the so-called problems with the B-2 are either so minor as to be operationally insignificant, or are expected occurrences at this stage of a complex weapon system's development and production.

CENTERFORSECURITYPOLICY: Center For Security Policy

"The development of this weapon is not intended to send a signal to any one particular country, " Pentagon press secretary George Little said.

WSJ: Pentagon Seeks Mightier Bomb vs. Iran

Determined to give effect to its unmet 31 July demand that Iran suspend all uranium enrichment-related and reprocessing activities, the Security Council today imposed sanctions on that country, blocking the import or export of sensitive nuclear materiel and equipment and freezing the financial assets of persons or entities supporting its proliferation sensitive nuclear activities or the development of nuclear-weapon delivery systems.

UN: Security Council

But in setting a timeline for development of an Iranian nuclear weapon that is longer than the more urgent one usually cited by Prime Minister Benjamin Netanyahu, Mr. Obama appeared to be tamping down any expectations for pre-emptive action against Iran while aiming to assure its closest Mideast ally of U.S. support.

WSJ: Obama Sets Timeline on Iran Nuclear Bomb

The new test is the latest weapon in WADA's arsenal following the development of tests for the endurance-boosting drug erythropoietin (EPO) and so-called designer steroids such as tetrahydrogestrinone (THG), which have been chemically engineered to deceive the testers.

CNN: Anti-drugs chief confirms HGH test

After the Soviet Union broke America's atomic monopoly in 1949, several prominent scientists and politicians favoured the development of the hydrogen bomb, a fusion weapon hundreds of times more powerful than the bombs that the Manhattan Project had built.

ECONOMIST: Robert Oppenheimer

And a sophisticated ballistic weapon the Navy was counting on to arm future warships was canceled by Army managers even though program development was nearly complete.

FORBES: Why The Army's New Combat Vehicle Is Doomed