Increasing attention is being paid to the "William Wilberforce Trafficking Victims Protection Reauthorization Act of 2008," signed into law by George W. Bush. I note that primarily because it was signed back at basically the last moment that immigration policy was bipartisan. Once President Bush left office, it disappeared.
Republicans want to amend the law to speed up the processing and removal of the children currently in the United States. As it stands, only children from contiguous countries are processed quickly. Since the surge of children is coming from Central America, they go under the authority of the Department of Health and Human Services, getting hearings and staying with families (sometimes their own) while they await a final decision. They get an immigration judge rather than a border patrol agent. That is why the Obama administration is asking to hire more judges, which are in embarrassingly short supply.
That is potentially a reason for the surge--word has spread that if children arrive in the United States, they are not immediately deported. As with other potential reasons, it suffers from timing--if the law was passed in 2008, why would it take six years for a surge? But it's possible.
But what should we do? There is evidence that from a humanitarian perspective, it's a mistake to treat Central American children like their Mexican counterparts. From Dara Lind (who has been writing a lot of interesting stuff at Vox):
It's not that Border Patrol agents aren't sympathetic to the plight of Mexican children — indeed, they're personally very kind to the children in their care. But the secret report shows that Border Patrol agents simply don't know what to look for to figure out if a child is being victimized, or what to do if he or she is.
It's a rushed, confused process that would become more even chaotic given the numbers we're dealing with. I tend to agree that we should treat children the same, but we should take the most humane approach, not the least.