When a rescue plan for Fannie Mae and Freddie Mac was hastily cobbled together over a weekend, the point man on the latest threat to the world economy was a 45-year-old Treasury official with little government experience.

The official, Anthony Ryan, was thrust into the front lines of the credit crisis after Treasury Secretary Hank Paulson's top assistant, Robert Steel, unexpectedly left to become chief executive of Wachovia. Steel had been a main architect of the Bush administration's response to the mortgage crisis. So when the shares of the two mortgage giants plunged on Friday, July 11, provoking fears of a meltdown, the job fell to Ryan, who led a team of a dozen people that came up with the bailout plan.

So far, he has received acceptable marks for putting the plan together. But the surprising wave of fierce resistance the plan initially drew from Congressional Republicans highlights the difficulties Ryan and the other top Treasury officials, all from the financial industry, face. They have little or no experience, working the levers of Congress.

Anthony Ryan • Assistant Secretary of the Treasury for Financial Markets. December 2006 to July 2008. • Previously, a partner of Grantham Mayo Van Otterloo & Co. • Before that, a portfolio manager at asset management firms including State Street Corporation and The Boston Company. • 1985 graduate of the University of Rochester. Masters Degree from the London School of Economics and Political Science in 1986. • Married, with four children.

Ryan had previously spent his entire career in the investment industry, most recently as a partner at Grantham Mayo Van Otterloo & Co., the Boston-based asset management firm co-founded by famed value investor Jeremy Grantham.

When Paulson, the former chief executive of Goldman Sachs, first came to Washington as Treasury secretary in May 2006, he brought along Ryan as an adviser. Exactly how this happened is not clear. In an interview with Portfolio.com, Ryan says he had never met Paulson before, although they knew many individuals in common, several of whom had recommended him to Paulson. The Treasury Secretary chose Ryan to help coach him for his Senate confirmation hearings, then brought him in when he took office.

Ryan clearly has less stature than Steel, who had been vice chairman of Goldman Sachs and who has wider and higher-level contacts in the financial industry that made it easier for him to get in touch quickly with key people during a crisis.

But supporters of Ryan say his brief time in government working with Steel and Paulson has not been an impediment.

"The last two years have aged him in experience like dog years," says Eric Mindich, a former Goldman Sachs trader and chief executive of the $12 billion hedge fund Eton Park Capital Management.

Mindich knows Ryan from a private-sector subcommittee of the President's Working Group on Financial Markets, an interagency council that was created after the stock market crash of 1987.

That group had been among Ryan's main roles, along with oversight of Treasury bonds and other financing. His job did not involve crisis management, dealing with Congress, or regulation of outside entities.

The new challenge has meant more than just a change in responsibilities. The housing and credit crises have pushed Ryan and other Bush administration officials into an unexpected regulatory, big-government role that conflicts with their long-stated free-market beliefs.

One aide to a Congressional financial committee say these officials suddenly find themselves having to fill the role that Franklin Roosevelt's brain trust did in grappling with the Depression.

In a series of speeches in recent months, Ryan has sharply criticized the financial-services industry for "the erosion of market discipline." He said this was a leading cause of the subprime meltdown.

Yet Ryan himself was instrumental in giving the same firms a central role in proposing the solutions. Committees under the aegis of industry organizations  like the Securities Industry and Financial Markets Association and the American Securitization Forum, are the leading groups charged with developing "best practices" concerning transparency and disclosure to investors of risks related to asset-backed securities.

Ryan says he sees no inherent conflict in this.

"Firms that benefited because they had better practices are sharing those with other firms. I do believe the leaders in the industry can drive the industry to improve their practices."

Neither Congressional Democrats nor Republicans have been willing to openly criticize Ryan and other Treasury officials for the way they handled the rescue plan for Fannie Mae and Freddie Mac. But some Republicans are concerned that the plan could put taxpayers on the hook for huge sums.

Democrats have backed the plan, and they have been quick to accuse Republicans of endangering the economy by opposing it. A spokesman for the House Financial Services Committee, chaired by Representative Barney Frank, Democrat of Massachusetts, insisted that the Treasury officials had been "very, very adept." He added, "Our being in government so long, and them being in industry so long, it sort of balances out."

House Republican leaders, stung by criticisms that their opposition to the bailout threatened the economy, have reversed course and endorsed the plan. A staffer for the Republican Study Group, an organization of more than 100 House members that promotes conservative economic policies, said he was not aware of any specific displeasure by members in the way the Treasury officials handled the plan, although some members still strongly oppose it.

But aides to two House members, one a Democrat, the other Republican, said earlier communication by Treasury officials on the plan might have avoided the initial conflict and delay of approval, which is now not expected until sometime this week.

To enhance Ryan's clout in helping Paulson deal with the current problems, President Bush nominated him, even though only six months remain for the administration. The Senate, however, has not scheduled any confirmation hearings, and it will probably will not before the summer recess in early August.

Treasury spokeswoman Jennifer Zuccarelli said "we're keeping Congress fully occupied right now" dealing with the bailout plan.

Ryan says that when Steel told him he was leaving for Wachovia, he took his successor aside and told him, "Look, the Secretary has your confidence, your colleagues have confidence in you. Just continue to believe in yourself, and know that you have a great team."