$679 million (by NASA) vs $69 million (ISRO) doesn't justify that. This has been proven over and over again by Spacex: http://blogs.scientificamerican.com/observations/2011/09/28/...

US govt. throws money at it.

I think there have been a lot of lessons learned and tech transfer from earlier lunar and Mars missions. Chandrayaan-1 involved a lot of experts from NASA and ESA, for example, because both agencies had instruments on board. (I'm acquainted with one of these payload specialists.)

Some of the willingness to do that tech transfer is basically boosting India as a counterweight to China's space ambitions.

Also, remember that Chandrayaan-1 failed early. It's a steep learning curve.

no I think we should think of that good old "the NASA space pen" vs. "the russian pencil" analogy.