Natural disasters in Central America, economic devastation, gang wars, political oppression, and a new administration are all driving the sharp rise in U.S.-Mexico border crossings — a budding crisis for President Biden.

Why it matters: Migration flows are complex and quickly politicized. Biden's policies are likely sending signals that are encouraging the surge — but that's only a small reason it's happening.

The Centers for Disease Control is allowing shelters handling child migrants who cross the U.S.-Mexico border to expand to full capacity, abandoning a requirement that they stay near 50% to inhibit the spread of the coronavirus, Axios has learned.

Why it matters: The fact that the country's premier health advisory agency is permitting a change in COVID-19 protocols indicates the scale of the immigration crisis. A draft memo obtained by Axios conceded "facilities should plan for and expect to have COVID-19 cases."

House Minority Leader Kevin McCarthy (R-Calif.) has requested a meeting with President Biden to discuss the rising numbers of unaccompanied migrant children at the U.S.-Mexico border, in a letter sent on Friday.

Why it matters: Biden is facing criticism from the right and the left as agency actions and media reports reveal spiking numbers of migrant children overwhelming parts of the U.S. immigration system. Recent data shows an average of 321 kids being referred to migrant shelters each day, as Axios reported.

Just over a month into his presidency, President Biden is staring down a mounting crisis at the border that could be just as bad as the ones faced by Barack Obama and Donald Trump, if not worse.

Why it matters: Immigration is an issue that can consume a presidency. It's intensely and poisonously partisan. It's complicated. And the lives and welfare of vulnerable children hang in the balance.

Comprehensive immigration reform is a pipe dream, but some Senate Democrats are hoping to tie key immigration provisions to the next big reconciliation push.

Why it matters: Immigration is one of the most controversial and partisan issues in U.S. politics, which is why the budget reconciliation process — which allows for bills to pass the Senate with a simple majority rather than the usual 60 votes — is so attractive.

Fresh internal documents from the Department of Health and Human Services show how quickly the number of child migrants crossing the border is overwhelming the administration's stretched resources.

Driving the news: In the week ending March 1, the Border Patrol referred to HHS custody an average of 321 children per day, according to documents obtained by Axios. That's up from a weekly average of 203 in late January and early February — and just 47 per day during the first week of January.

Immigration was found to be the most polarizing issue in America based on new polling from Populace.

Why it matters: Americans have surprisingly similar priorities for the U.S., but immigration stands out as one of the few issues with clear partisan differences. It underscores the challenge for advocates and lawmakers hoping to pass immigration reform in the coming weeks amid narrow margins in Congress.

A briefing scheduled for President Biden this afternoon outlines the need for 20,000 beds to shelter an expected crush of child migrants crossing the U.S.-Mexico border, Axios has learned.

Why it matters: The rapid influx of unaccompanied children is becoming the administration's first new crisis. A presentation created by the Domestic Policy Council spells out the dimensions with nearly 40 slides full of charts and details.

Civil rights advocates are preparing to mark the first anniversary of Selma's "Bloody Sunday" without the late Rep. John Lewis, and as the first anniversary of George Floyd's death approaches. 

Why it matters: A three-day virtual event seeks to acknowledge aging civil rights activists who pushed the nation to expand voting rights in 1965. It also comes as a new generation of advocates fights against voter suppression proposals and pushes police reforms.

Secretary of the Department of Homeland Security Alejandro Mayorkas announced Monday that the Biden administration will explore "lawful pathways" to allow migrant families separated under the Trump administration to reunite in the U.S.

Why it matters: Biden has pledged to reunite the hundreds of families still separated as a result of the Trump administration's "zero tolerance" policy, and signed an executive order last month creating a family separation task force chaired by Mayorkas.