Washington (CNN) With the ascension of former Sen. Jeff Sessions to attorney general and several of his former staff installed at the White House and federal agencies, immigration policy experts are sensing a sea change in Washington.

Advocates and policy staff of both parties half-jokingly refer to the "Sessions cabal" that has now found power in President Donald Trump's Washington -- a group that for years has found itself outside the mainstream on immigration policy in Washington and faced ire from their Republican and Democratic colleagues for what one sparring partner called "strident" positions.

As the senator from Alabama, Sessions and his staff regularly aligned with staff of Iowa Sen. Chuck Grassley, the Republican chairman of the Senate Judiciary Committee, and the staff of House Judiciary Chairman Bob Goodlatte, a Republican from Virginia. Those offices were also key allies of groups that advocate restricting legal and illegal immigration, including the Federation for American Immigration Reform (FAIR), Center on Immigration Studies and NumbersUSA.

Already, a network of former Sessions staffers and like-minded allies have made an impact on the administration. When Trump rolled out his controversial travel ban, it caught Congress and many of the agencies that would implement it by surprise. The administration maintains that it worked with the Department of Homeland Security on the order. But according to sources familiar, the coordination largely amounted to two former Sessions staffers -- Stephen Miller in the White House and Gene Hamilton at DHS -- working together mostly without the knowledge of other rank and file and leadership at DHS.

For years, the loose coalition held a hardline position on illegal immigration as well as a desire to restrict legal immigration, as well.

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