How many apprehensions at the southwest border will the US public tolerate before treating it as a 'crisis'? Put another way, at what level do migrant apprehensions become a political problem for an administration?

As it turns out, this number can be reasonably estimated. As a rule of thumb, Americans will accept southwest border apprehensions less than 500,000 / year as normal, that is, about 40,000 / month. If we allow for seasonality, then 50,000 / month is acceptable in the peak season of March to May, and 30,000 - 40,000 / month for the rest of the year, as we show on the 'Tolerance Limit' line on our graph below.

Using this framework, we can easily identify the respective border crises of Obama, Trump and now Biden, as well as incipient surges in late 2018 and again in late 2020 (and a pre-Trump surge in late 2016). The model accurately shows those periods when the media and the analyst community viewed border apprehensions as being at crisis levels.

If the Biden team wants to put the border crisis behind them as a political matter, they should be targeting no more than 50,000 monthly apprehensions at the southwest border to May and 40,000 / month thereafter.

We are a long way from there.