Where do you draw the line on this? Should all newcomers be subsidized? Every YC startup that wants to enter the automobile sector should be federally subsidized? What about newcomers in other industries like healthcare, banking, and mining? Should those be subsidized too?
Wherever the elected officials want to. Generally it is a big hammer and is applied to sectors, so there is an expectation of low success rates. That is why the government is doing it, and not private investors. This time they supported the "green" technology sector through allowing companies to apply for low interest loans, and giving consumers tax credits for those items. The next elected administration / congress might try to encourage the airline industry with fewer fuel taxes, the clothing industry with import tariffs, or support USPS by taxing the internet. You never quite know what they might do, you just hope they don't do it for very long.
In the right place.
EDIT: HN really can't take a joke. Sigh
I don't know why you think it would be heretical to say this.
Government intervention in and of itself is neither good nor bad. It can be used well, and it can be used badly. But at the end of the day, it is just a tool.
In the case of emerging technology players going up against incumbents, the government should absolutely intervene and help the newcomers.
In the case of established markets such as agriculture, the government should stay the fuck away and refuse to subsidize anything.
I mean, seriously... when it comes to spending taxpayer money, the thought process should be purely pragmatic. We should think about the result we want to achieve, and then determine whether we need government intervention to achieve it.