Imagine if, long ago, we established not only an FDA for drugs, but also a parallel agency for software. The software industry's FDA would exist in order to protect computer users from bad programs - harmful, or low quality - and would require central approval of every single program writter. Of course this would produce grumbling for software engineers who just want to make a living, but the arrangement would indeed allow software-FDA to stop nasty malware before it made it onto the market.
Unfortunately, software-FDA then becomes inconsistent and over-conservative - always more reasons to say no than yes - and hurts computer users in the long run by decreasing the number and quality of programs available to them. For example: programs released back in the 1980s, even if they slowed your computer down and crashed all the time, would be allowed to remain by an unspoken grandfather agreement (too messy to recall them or investigate them now!) The old-school software makers would certainly not rock this boat, and the newer software companies wouldn't speak out for fear that they would be punished by software-FDA. The rules that you had to follow when developing software would be so byzantine that software companies would have to hire their own legal experts, who are expensive and say "No" a lot to developers' plans. Needless to say, it would be very hard for small software companies to survive, and software would cost more for consumers.
Meanwhile, new programs would be scrutinized even for infrequent damage, i.e. to one out of a thousand computers, and if the programmers couldn't explain exactly how the programs worked in every situation, they wouldn't be allowed to sell them. (Nobody knows how the old programs work, but they're still allowed to be sold; and certainly nobody is allowed to make an informed choice about the acceptable risk to them. The software consuming public doesn't understand enough to make these decisions.) Investors in new software companies are scared off by any program that shows real innovation, and the number of programs released per year starts to drop. Finally, the software-FDA does allow computer technicians to sell programs to consumers for uses other than for what the programs are specifically approved to do - even though software-FDA clearly doesn't trust these same technicians to evaluate whether the programs should be on the market in the first place. But people get used to this crazy inconsistency, so hardly anyone says anything.
And there would be a whole other government agency (the software-DEA), for the worst programs of all. There are certain programs, software-DEA says, that are SO BAD that they don't trust ANYBODY to use them responsibly - consumers OR computer technicians - so they put people in jail for buying and using them. Software-DEA even puts people in jail when these programs harm only the consumers' own computers, by their own consent. In fact software-DEA keeps putting people in jail even when some of the programs have been conclusively shown by computer scientists NOT to harm their computers. Not surprisingly, a black market will form around these programs, some of which are fun to use and pretty safe, and software-DEA will say, completely bass-ackwards, this proves these programs are bad, and must be kept illegal.