Trent Lott couldn't force his Republican colleagues to do anything when he was Senate majority leader, but he surely had his arsenal of sticks and carrots. If a member – even a fellow Republican – was going to disrupt the progression of a bill by offering a problematic amendment, Lott would "fill the tree," loading the bill with other amendments so the rogue member couldn't add his own. He once threw Arizona Sen. John McCain out of a meeting because of his language. He held votes on Mondays and Fridays to make sure senators stayed in town to work. And he had little presents to parcel out to those who worked and played well with others.

"I revere the institution but I also knew all the nooks and crannies," says former Mississippi Sen. Lott, whose decades-long Capitol career includes time as a staffer, House member and Senate GOP leader. "I knew where all the [private office] hideaways were, and all the parking spaces. And I meted them out carefully."

House Speaker John Boehner, meanwhile, lost a power struggle with the relatively new rank-and-file conservatives in his caucus, whose repeated efforts to disrupt the schedule and institution led the veteran Ohio lawmaker to announce he would leave his seat at the end of October. Despite holding the gavel and being third in line to the presidency, Boehner simply could not keep his members in line. With so few ways to pressure off-the-reservation colleagues, Boehner once offered the tame punishment of refusing to allow those lawmakers to sit in the speaker's chair and preside over the House, recalls former Rep. Steve LaTourette, an Ohio Republican.

"Nobody wants to do that anyway," LaTourette says, recalling the private meeting where Boehner came up with the ineffective sanction against disruptive fellow Republicans. But for an exasperated Boehner, experts and colleagues on both sides of the aisle say, there wasn't much else he could do.

Being a leader in Washington just doesn't carry the heft or mystique it used to, longtime lawmakers and policymakers say. The Senate that once quaked at the power of Majority Leader Lyndon Baines Johnson now has a freshman member, Texas Sen. Ted Cruz, who called his own GOP leader, Kentucky Sen. Mitch McConnell, a liar on the Senate floor. In the House, congressmen once worried about being shut out of a strategy session or denied funding for a community center in their districts. Now, a group of low-seniority conservatives are gloating over their success in exhausting the patience, and the tenure, of a speaker who has served a quarter-century in the House.

There is no fear factor on the Hill anymore – whether it means bucking the leadership, scheming to shut down the government or refusing to raise the debt ceiling, resulting in a costly drop in the nation's credit rating. And that has made the job of a leader far more aggravating for those who, in the vernacular of Lott's book title, are in the business of "herding cats." It's also made such posts less appealing: California Rep. Kevin McCarthy is the leading contender to replace Boehner with only limited competition for the post.

Much of it, long-serving members say, comes from a unilateral disarmament on the part of party leaders. The elimination of earmarks, for example – small pots of cash doled out for specific projects in individual districts – took away the power of both party leaders and appropriations committee chairs to wheedle votes and cooperation from rank-and-file members. Such allocations, a very small part of the budget, were banned because they gave the appearance of a political payoff or corruption.

"Not only were people afraid of their leaders, but they were afraid of the appropriations committee chairs," LaTourette says. "When you don't have the earmarks, what are you going to do? You can't kill anybody." Earmarks, LaTourette says, "used to bring some people to heel."

In fact, says Rep. Michael Capuano, a Massachusetts Democrat, the projects are still there. They're just controlled now by the executive branch, removing authority from both congressional leader and the legislative branch as a whole.

"Leadership doesn't have much to give. They have voluntarily given up their power and their points of leverage, such as doing favors for people, constituent stuff," Capuano says. "There used to be a whole chain of things they could do. What can leadership do for members now? Get them on a committee? Even that doesn't mean anything. Committee chairmen don't have as much juice around here as they used to."

That's true in the Senate, too: when the chairmanship of the Appropriations Committee opened up in 2012 the next two senators in line for the post declined to take it.

Party leaders also have lost a lot of control over their members' job security, notes Elaine Kamarck, director of the Management and Leadership Initiative at the Brookings Institution. Senior members of the party could help bankroll a struggling campaign, or discourage others from entering a primary against an incumbent. But the explosion of contributions and spending by super PACs and other outside groups has dramatically diminished the power parties have in rewarding and protecting their own (something former House Majority Leader Eric Cantor found out when he lost his Virginia GOP primary last year to now-Rep. David Brat).

"That's the real problem – they just don't have any focus of control. It's all outside the Congress, it's not inside," says Kamarck, who served as senior adviser to Vice President Al Gore. "You probably have talented politicians, as we always did, but they have no tools. And so there are real limits as to what they can accomplish."

Former congressman Charlie Bass has seen both ends of the spectrum in the power of party leaders vs outside groups. After winning a crowded GOP primary in 1994, Bass was surprised to get a visit from Boehner, then a relatively new member of Congress. And he was even more stunned by the $1,000 check Boehner had with him to help Bass' campaign. "I thought I was a millionaire! No one had ever given me a check like that," recalls Bass, who ended up becoming a Boehner friend and ally in the House.

Three years after Bass lost re-election in 2006, Boehner approached him again, coming to Florida to convince Bass to run in a more GOP-friendly 2010 election year. Bass won, but this time, it was outside cash that drove the day. The campaign budgets of Bass and his Democratic opponent together were outspent two-to-one by outside groups, Bass says. That meant neither candidate had full control over their respective campaign messages.

And once in office, Bass says, lawmakers – especially those in politically homogenous districts where the primary effectively determines the outcome of the election – may feel more beholden to those groups than to their political leadership. And that, he says, makes it awfully hard to convince them to keep the government running or salvage the nation's credit rating.

After previous shutdowns, "the country has gotten used to this kind of irrational behavior, and it's always worked out," so there's no fear of trying such tactics again, Bass says.

Lott decries a lack of "maturity" in Congress, both in terms of years of service and leadership training (McCarthy, for example, has never been a committee chair). And others agree that the structural weakness of the leaders has enabled cocky behavior.

In an earlier era, new members "came here and wanted to get a sense of the institution" before taking the lead on something, says Sen. Dianne Feinstein. The California Democrat had criticized Sen. Tom Cotton, an Arkansas Republican, for penning an "open letter" to Iran in the middle of negotiations on an arms pact – and after Cotton had been in the Senate less than three months. "They didn't want to immediately stop everything – that's what's changed."