Labels are more or less arbitrary, and people coin new labels all the time; could I not just coin a different word to label my political and economic beliefs? "Democratic mutualism" springs immediately to mind, or — if we can have Marxism and Fabianism — why not Larryism? I hereby proclaim myself the first Larryist! I can describe Larryism while standing on one leg: social ownership of capital and true democratic* government. The rest is implementation detail.
*I mean "democracy" in the sense of rule of the people, as opposed to republicanism, the right of the people to choose their rulers.
The problem is at one level similar to the "toilet" problem: we are generally uncomfortable with urination and excretion, yet we must at times actually discuss these topics, so we coin euphemisms to refer to the activities and their corresponding apparatus. But because we always use some consistent euphemism, the euphemism itself becomes the primary denotative term, and acquires the discomfort and embarrassment we were trying to avoid in the first place.
There's a similar problem talking about communism. Regardless of whatever else they did, and why they did it, it is difficult to deny that the social ownership of capital was an important part of what Lenin, Stalin, Mao, et al. were trying to do. In a world where even a style of mustache is now virtually unknown because of the (deservedly) poor reputation of one of its wearers, just having a superficial similarity to people of bad reputation earns accusations of identity.
Indeed the modern sense of "socialism" was promoted in no small part to avoid the unpleasant associations of "communism". But, as we have seen, "socialism" carries a burden of guilt by association; perhaps not quite as heavy as "communism" but still quite severe indeed. It's to the point today where just because the government is taking measures for the direct benefit of the people, measures historically and ideologically entirely compatible with capitalism, an entire political movement has formed opposing these measures as "socialist", to mean identical with the worst alleged excesses of Stalinism and Maoism.
I'm damned if I do and damned if I don't: If I call myself a communist, I'm in the same "political category" (whatever that means) as Stalin and Mao, and it's assumed I want to do everything those leaders did — and were alleged to have done — including even the parts that contradict the other parts. If I don't call myself a communist, the substantial similarity between my ideology and these historical communists not only creates just as much guilt by association but also opens me to accusations of disingenuity and outright mendacity: not only am I "really" a communist, I'm a crypto-communist!
It's important also that alleged violations of human rights by communist governments and their "undemocratic" nature do not and have never motivated the capitalist ruling class's or Western government's opposition to communism. Their constant and enthusiastic support of undemocratic dictators perpetrating egregious human rights violations &mash; Augusto Pinochet, the Shah of Iran, Ferdinand Marcos — and their violent overthrow of democratically elected leaders — Allende, Mosaddegh — gives lie to this assertion. We were allies with the Soviet Union in the Second Imperialist War, and China had only to change its economic system, without much ameliorating any of the political or human rights issues of the communist government, to earn rapprochement with the West. All the opposition to communism has been clearly motivated by the capitalist ruling class's desire to retain privilege and power.
I prefer to grasp the nettle firmly. I am a communist, and I reserve the right to define the term as I please: I will not have any definition thrust upon me willy-nilly. And if others who have accurately described themselves as communists (have at least given lip service to the tenets of Larryism) have done Bad Things, well, so much the worse for them: they were bad communists. Just as with atheism, communism is no silver bullet, no panacea for all the worlds ills; an asshole who calls himself a communist is just as much an asshole as one who calls himself a capitalist, a fascist or a Libertarian. I strive to be a communist who is not an asshole.