There are multiple ways to make it easier to register people to vote that don't involve enabling independents to hijack a party's primary. Automatic registration, for one.
Heck, I'm in the "automatic registration, vote by mail and polling station, early vote, free government issued voter ID cards" level of voting.
I want people who actually support the goals of the Democratic party and who have a long term interest in the goals of the Democratic party to choose who actually leads the Democratic party - if you can't remember to change your registration a month before the election, then I really don't feel that bad.
Yeah, the six month deadlines in New York are stupid, but so is the idea of letting a bunch of Republicans or wacky college anarchists voting in unelectable candidates on the local and state level.
A) There's never been evidence that trying to sabotage the opponent's primary has ever been more than 2-3% of the total vote (even in small primaries) and B) those wacky college anarchists are why you have 8 years of Obama.
I don't really see how closed vs open primaries makes a difference with same-day registration, given that you can switch the day of anyway?
Same day registration I have no problem with, but under Sanders' demands someone can show up to their polling place, refuse to register at that time as a Democrat, and still get to vote in the Democratic Party contest. Screw that, if you can't be bothered to register as a member of the party THE SAME DAMN DAY you're showing up to vote in that party's primary then you have no business voting in their primary contest.
But apparently we need to clear up some misconceptions about "independent voters"
There basically aren't any.
http://cookpolitical.com/story/6608
In fact, true independents are equally as down on Sanders than Clinton.
http://fivethirtyeight.com/features/sanders-isnt-doing-well-with-true-independents/
The problem with this analysis, however, is that most independents are really closeted partisans, and there is no sign that true independents disproportionately like Sanders.
Most voters who identify as independent consistently vote for one party or the other in presidential elections. In a Gallup poll taken in early April, for instance, 41 percent of independents (who made up 44 percent of all respondents) leaned Democratic, and 36 percent leaned Republican. Just 23 percent of independents had no partisan preference. In the last three presidential elections, the Democratic candidate received the support of no less than 88 percent of self-identified independents who leaned Democratic, according to the American National Elections Studies survey. These are, in effect, Democratic voters with a different name.
So let me clarify who you exactly are disenfranchising. You're disenfranchising (primarily young) democratic voters. Due to the mostly non-competitive nature of the Democratic primary + the candidates involved and their extreme demographic shifts this year - you're getting a ton of young folks to the voting polls for probably the first time in their lives by having open primaries and same-day registration, and since those voters tend to skew dramatically Democratic...congratulations, your policies have made it harder for the Democrats to continue to hold the advantage in presidential elections.
Let me make this clear; there has never been, despite everyone's bedwetting about the situation, any kind of "actual independents hijacking a primary" situation, ever. Everyone likes to think about it in theory, and everyone likes to use it as an excuse for when their candidate under performs (stares at this thread) relative to "expectations" (which are usually derived from someone's own personal bias and / or hatred / ignorance about how things work).
In fact:
http://www.thenation.com/article/what-everyone-gets-wrong-about-independent-voters/
 Both candidates’ supporters—and Donald Trump—have it mostly wrong. While around four-in-10 voters say they’re independents, very few are actually swing voters. In fact, according to an analysis of voting patterns conducted by Michigan State University political scientist Corwin Smidt, those who identify as independents today are more stable in their support for one or the other party than were “strong partisans” back in the 1970s. According to Dan Hopkins, a professor of government at the University of Pennsylvania, “independents who lean toward the Democrats are less likely to back GOP candidates than are weak Democrats.”
While most independents vote like partisans, on average they’re slightly more likely to just stay home in November. “Typically independents are less active and less engaged in politics than are strong partisans,” says Smidt.
Oh, also, just to further go into the "independents" train...and how it leads to a net loss for Democrats to keep "independents" out of the political process.
 In that sense, we’re talking about precisely the kind of people who should be encouraged to participate in the primary process. Most Dem-leaning independents have as much invested in the Democratic Party as a typical registered Democrat—they vote consistently for its candidates. At a minimum, this should call into question highly restrictive primary rules like New York’s, which had a deadline to switch parties that passed last October, months before most people were paying attention to the primary contest.
At the same time, Sanders’s superior performance among independent voters is largely a matter of demographics, not the fact that they identify as independents. Younger people, whites and men—groups that skew toward Sanders—are significantly more likely to identify as independents than older voters, people of color and women.
Among partisan Democrats, Clinton’s supporters tend to be more moderate than those backing Sanders, but there’s virtually no ideological gap between the two candidates’ independent supporters. That’s consistent with Pew’s broader finding that the ideological “positions of those who identify as Democrats and those [independents] who lean toward the Democratic Party are nearly identical.” And while 8 percent of Dem-leaning independents have a “very negative” view of the party, according to Pew, that’s also true of 4 percent of those who identify as Democrats.
Millennials have played an outsized role in Sanders’s success. According to Pew, they’re the group that’s most likely to identify as independents—almost half of them do—but when pushed, they’re also the age cohort that leans most toward the Democratic party. That’s especially true among younger people of color. White millennials are almost evenly split in their partisan leanings—they favor Republicans by a 45-43 margin—while non-whites in this age group identify as or lean toward Democrats by a massive 61-23 margin.
There's definitely some degree of people deciding what is "right" based on what they perceive as benefiting their preferred candidate. This primary season I've seen some Clinton supporters defend New York's six-month deadline for changing party registration, while some Sanders supporters have attacked early voting.
Yeah. The fact that young voters skewed heavily for Sanders and that the pro-Hillary folks are all on board with suppressing voter turnout for that group is pretty appalling. This is like folks wanting the assault weapons ban (aka the scary looking guns ban) re-instated after Orlando and people on the no-fly list not able to buy guns - it is obvious none of them have actually read the assault weapons ban and/or have not realized that the shooter wasn't on the no-fly list.
Regarding the assault weapons ban
http://fivethirtyeight.com/features/guns-like-the-ar-15-were-never-fully-banned/
The AR-15 used to be illegal. President Bill Clinton’s assault weapons ban, which was in effect from 1994 to 2004, banned the AR-15 and other guns that were too similar to military-style weapons. However, this law did not prohibit Americans from owning semi-automatic weapons; it capped how many military features an individual gun could have. During the ban, a semi-automatic rifle like the AR-15 could legally have any one of the following features, as long as it didn’t have two or more of them: a folding stock (making the gun slightly easier to conceal), a pistol grip (making the weapon easier to hold and use), a bayonet mount, a flash suppressor (making it harder to see where shots are coming from), or a grenade launcher.
A 2004 report commissioned by the Department of Justice on the effects of the assault weapons ban concluded that the law was largely ineffective at limiting access to weapons with the power of the AR-15. According to the report, the ban focused on “features that have little to do with the weapons’ operation, and removing those features is sufficient to make the weapons legal.” The report noted that several semi-automatic rifles were functionally equivalent to the AR-15 and untouched by the ban. It’s hard to know whether Mateen’s AR-15-style weapon would have been covered by the old ban, though some versions of the Sig Sauer MCX rifle he used are sold with more than one of the components that were limited by the law. Depending on how many military-style features the rifle had when he bought it, it might have been legal under the assault weapons ban. And he would have been able to modify the gun himself, even under the old law.
Also - the shooter didn't have an AR-15; he had a Sig Sauer
