Here's why.
1. First of all, President Trump, like it or not, was elected with this as one of his primary issues. Clearly, a very significant portion of voters support the action.
2. It's 5 - 6 billion dollars for cripes sake! That's a drop in the ocean. The government wastes hundreds of billions of dollars on all kinds of items that are highly questionable, if not, useless. Even if there is a small possibility of it making a positive impact, it's worth taking a flier on. Just do it already.
3. There are already walls or barriers all up and down the southern border. Ever been to El Paso? In principle we don't let people just walk freely over the border. Not the Canadian Border. Not the Mexican border. What the Hell is the difference in adding a little more barrier? In addition, we have always had border patrol to control crossings as well. Bottom line is that some additional barrier (whether you think it is effective or not) is something we have always done, will continue to do and both parties have always been more than willing to fund.
4. I completely reject the idea that increasing barriers to prevent uncontrolled crossings is somehow racist. This is just silly and not an intelligent position. Again, we already do this. We have laws on the books to prevent it. If there were a similar problem on the northern border, we would do the same thing. Well, actually we already do. Crossings at the northern border ARE controlled. It's just that additional measures are required in different places to effectively control it.
5. Nobody is proposing that we don't let people in from Mexico, Honduras or wherever. The point is to just make it a controlled and documented process. This is a reasonable position that reasonable people should be able to agree on. I'm sure they do in fact.
6. It is pretty obvious to me that this is all political posturing. The Democrats are being obtuse because they don't want to give Trump a "victory". This is just silly. Fund the damn thing already and move on. Is it really worth all of the hand-wringing and entrenching themselves into immovable positions?
It's just frustrating and I'm tired of hearing about it. It's just plain stupid. Fund it and move on.