This isn't true. For example, the White House had been intentionally silent on the issue of SOPA until two petitions pushed it to take a stand, which had a not small impact on the outcome of the legislation.
http://www.whitehouse.gov/blog/2012/01/14/obama-administrati...
> The most reasonable petitions get essentially the same reaction, however. ["Legalize pot? I think we can guess what they were smoking when they signed that one! Hahahaha!"]
Please cite examples. I am aware of two responses to marijuana legalization petitions. Both were reasonable, respectful, and laid out why the White House disagreed with the petitioners.
https://petitions.whitehouse.gov/petition/support-law-protec...
https://petitions.whitehouse.gov/petition/legalize-and-regul...
Petitioning, per se, has always been a sort of plea, a supplication to the ruler that he should pay attention to something. You bring the petition to your ruler, he reads it, and then does what his conscience suggests him to do (which might be to prosecute every single signatory, for what we know). This hasn't changed. Petitions are tools to get topics "on the radar", providing another datapoint to decision-makers; nothing more, nothing less.
If you want direct democracy, then you need a website where you can propose laws and force the legislative branch to actually vote on them. This is a nice idea in theory, but in practice it's a quagmire waiting to happen (unless you really want laws glorifying Anonymous or public buildings dedicated to moot).
I'd argue that they should determine what they whole electorate wants... but they should be striving for what their whole electorate needs. It may not get them re-elected, but getting re-elected isn't "supposed" to be their job, doing what's best for the people they represent is.
Sadly, none of that seems even close to common practice.
Unfortunately, the few alternative models emerging in the last century (usually just variations on one-party rule, really) backfired quite spectacularly, so we're nowhere near finding better solutions to the problem.
Although it's by no means perfect (what is?), it does help solve the problem of special interests being able to buy politicians.
If you live in the United States you have a congressperson. Contacting them is a much more reasonable place to start.
Venting that effort into something that doesn't work at all does not strike me as a net positive.
I'm sure some people like the idea of being able to successfully demand that individuals in government be fired through the petition system, but that seems like a Pandora's box if ever there was one.
Having higher levels of serotonin makes us more blind to unfairness:
http://www.sciencemag.org/content/320/5884/1739.abstract
> We observed the effects of manipulating 5-HT function on behavior in the ultimatum game, where players must decide whether to accept or reject fair or unfair monetary offers from another player. Participants with depleted 5-HT levels rejected a greater proportion of unfair offers, but not fair offers, without showing changes in mood, fairness judgment, basic reward processing, or response inhibition.