Most of the problems Jordan faces today are the direct result of regional instability caused by others -- including the U.S.
When King Abdullah visits the U.S. to ask for help, he's actually demanding (politely) that we help him deal with the mess that WE created over there.
Jordan does have an interest in this conflict.
The declared aim of these jihadis is to conquer the Islamic lands and unite them into a single Caliphate. Then to conquer the world, in the name of God, and impose Sharia (Islamic law) globally. This is the great cause that they use to recruit foreign fighters to join them.
As they talk (in Arabic), the Jordanian Government listens. Many of the jihadis are themselves Jordanians, so this is a debate within their own communities, indeed within many families in Jordan. An earlier leader (Abu Musab al-Zarqawi) of what has now become ISIS, was a Jordanian, so they know his family and tribe quite well.
For those familiar with the thinking in Jihadi circles, Jordan is next, after Syria and Iraq. They propose killing the King, and his family. They are obviously quite serious about killing.
“Most of the problems Jordan faces today are the direct result of regional instability caused by others — including the U.S. “
I would say that is true, but it is always the case in the unstable Middle East. Turkey has provided the main military assistance to ISIS and other groups which have destabilized Syria. Qatar and Gulf Arabs have funded it. The US emptied the prisons (Camp Bucca Confinement Facilty) in 2009 of the al Qaeda in Iraq members, who now form the backbone of ISIS (including their Caliph, Abu Bakr al Baghdadi, and their top military commanders). The US also apparently covertly allowed/assisted the provision of munitions through Turkey to “rebel groups” in Syria, much of which ended up with ISIS.
Regardless of why this threat is at Jordan’s borders, and infiltrated within it’s population; it is an existential threat to the Jordanian state, the Jordanian people, and the King’s own life.
I posted earlier about how the King needs the President to authorized expedited processing of Foreign Military Sales to conduct a sustained air campaign - they can only buy or receive the advanced munitions that their jets use with export control approval from the USA.
Also, Jordan did earlier attempt to let the US handle the situation. CENTCOM established a presence in Northern Jordan, and has been training and equipping Syrian rebels.
It is a common (and rational) attitude to let Americans do the fighting and pay the bills. Everyone (except Americans)would prefer that.
The situation is just becoming more dire, and more of a domestic political issue/crisis within Jordan. The King has to deal with it now.