Let's start with the caveat that all Republicans believe Obamacare is horrible and that the law is wildly unpopular with a majority of Americans.

Now that that's out of the way, let's also admit that – even as the first shot has been fired in the GOP's congressional war against Obamacare – the defund scheme is (unfortunately) absurd. I know it, you know it – hell, the people pushing it know it. So why are so many grassroots conservatives convinced it's a good idea? Well, for a bunch of reasons:

1). A bias toward positive action. I'm reminded of a story from the Old Testament: in Numbers, 12 spies are sent to scope out the promised land; having surveyed the terrain, most of them return to the wilderness with bad news – that they cannot take the land. This is called an "evil report", because it was essentially a rebellion against God's promise.Only Joshua and Caleb delivered a positive report – and they were the onlytwo from their generation to make it into Canaan.

Now, as far as I know, conservatives don't have a divine mandate to reject Obamacare, but they may have a similar "shoot the messenger" mentality to the Israelites. Grassroots conservatives are eager to hear a positive report; they have no tolerance for a realistic appraisal. And this has much to do with whom they choose to believe …

2). Follow the leader. Many Tea Party activists and grassroots conservatives understandably outsource their research to trusted leaders. After all, these conservatives are busy with families and work to look into the byzantine rules of whether or not the Senate could even filibuster to defund Obamacare, etc. If a trusted leader like Rush Limbaugh or Ted Cruz assures them that this can be done – and that the only problem is wimpy Republicans who just need to grow a pair – then they believe it. I don't buy the notion that "the masses are asses"; instead, I think conservative leaders have a greater responsibility to shoot straight with their followers and not to exploit them for selfish fundraising or public relations purposes.

In fairness, some conservative leaders probably do see this as a negotiating strategy. In other words, in their heart of hearts, they know they can't defund Obamacare, but they think raising a stink over this issue might help them cut a better deal somewhere else. There are problems with this. For one thing, feigning a belief in the irrational requires not just fooling your adversaries, but also fooling your own friends (whom you've misled – used as pawns – by raising their hopes for a quixotic cause.)

3). They don't respect their opponents. It's a good idea to have a good, healthy respect for the other guy. After all, they are pros, too. They get paid to win, too. But consider this from National Review reporter Robert Costa, who is known for his excellent sourcing within the GOP:

There is a widespread, [Ted] Cruz-inspired consensus among many conservatives that [Obama] will cave, if only pushed by grassroots.

But grassroots conservatives seem to lack the ability to put themselves in the other guys' shoes. Grassroots conservatives should ask themselves this question: if you were Obama, would you allow Republicans to bully you into defunding the only landmark legislation you'll probably ever pass? If you wouldn't cave, why do you assume he will?

4). No sense of history. In the last decade, we've seen a couple of waves of immigration into the conservative movement. The first wave was largely after 9/11, and the second wave was in the wake of President Obama's election. Many of these newly-minted conservatives lack historical perspective. Sometimes, this is actually a good thing. But sometimes, experience in politics really is a benefit: sometimes, "wise old men" really are needed. And those of us old enough to remember the last government shutdown, when Newt Gingrich and Bill Clinton played this high-stakes game and Clinton won, probably have more realistic expectations concerning which side will get blamed.

Yet, a lot of folks supporting the defund effort seem to have a delusional belief that Democrats will somehow get blamed if there is a government shutdown. And they assume that just because people don't support Obamacare, they will support this scheme. (This, of course, is a logical fallacy.)

5). The "Sir Galahad theory of politics". Part of the problem is that they adhere to what conservative leader (and my former boss) Morton Blackwell calls the Sir Galahad theory of politics, which says: "I will win because my heart is pure." In other words, since Obamacare is self-evidently bad, we can't lose. This, of course, is a misunderstanding of the real nature of politics. Consider Barry Goldwater's failed campaign, which was premised on the notion that "In your heart, you know he's right."

6). They've given up. A lot of conservatives are understandably frustrated. They believe they are losing their country, and want something to be done about it right this minute. Now, I might argue that the defund Obamacare effort is actually counterproductive to their goals. This is because: a) it can't be done; and b) trying to defund Obamacare might have the unintended consequence of costing Republicans at the ballot box. My opinion is premised on the notion that the only way to stop Obamacare is to win elections and repeal it. Not only will procedural efforts to derail it not work, but they might also be viewed as an attempt at nullification.

7). Revolution is fun. Some of the activists involved in the defund effort do not see themselves as statesmen or as participants in the normal business of democracy, but rather as revolutionaries. This probably has to do with the rise of a more libertarian flavor of conservatism (some of these folks have read too much Robert Heinlein and Ayn Rand), as well as the fact that many of the recent influx of immigrants into the conservative movement came from the left (and have co-opted the Saul Alinsky playbook – which is a disturbing trend, inasmuch as he dedicated his book Rules for Radicals to Lucifer).

In any event, one gets the sense that grassroots conservatives seem themselves as being part of a new, romantic cause. And let's be honest, it is much more romantic – much more fun! – to try to destroy something via guerrilla means than it is to work within the system to change it. And here's something the leaders of Tea Party groups understand: young people are probably more susceptible to this sort of calling (see the "Uncle Sam" Obamacare ads).

There you have it: what I believe to be the seven reasons some grassroots conservatives are utterly convinced the defund Obamacare idea will work. This same sort of suspension of disbelief, no doubt, was at work when many conservatives were utterly convinced Mitt Romney would win the election last November.

So why does this matter? The problem with not learning your lessons is that you tend to repeat your mistakes. The GOP base needs to gain some insight into its behavior here. Otherwise, if it lets its "id" drive this response to Obamacare, it's going to end up in another political train wreck.