This week’s showdown in the U.S. Senate between the newly elected, Tea Party-supported Republicans and so-called “Establishment” GOP legislators was a preview for how business may be conducted in the next Congress. Two issues in particular have arisen in recent days that have even more clearly drawn these battle lines: earmarks, or the largesse that congressmen and women insert into legislation to benefit their state or district, and defense spending. Earmarks account for between one and two percent of the current federal budget. Though a relatively small part of annual outlays, they represent a very important and timely symbol of conservative resolve to get discretionary spending under control.

Conservatives and libertarians agree that there should be cuts to domestic “entitlements;” but as is often the case, one lawmaker’s earmark is another’s infrastructure project — often accompanied by hundreds, if not thousands, of good-paying jobs. Few in the U.S. Senate exemplified the conflicted nature of self-proclaimed conservatives more than the late Ted Stevens of Alaska. Living and ultimately dying as a flinty and occasionally prickly conservative standard-bearer, Sen. Stevens provided Alaska with billions of dollars in federal money (Alaska reaps five dollars for every one it sends to Washington), which he claimed supported forty percent of all jobs in the state.

Then there’s Senator Mitch McConnell, the current Senate minority leader, who in the years 2008-2010 sponsored over $1.5 billion in earmarks for his home state of Kentucky. He has been engaged in a rift with Kentucky’s incoming senator, Republican Rand Paul, who favors eliminating all such earmarks. In a big win for South Carolina Republican senator Jim DeMint and other Tea Party-inspired lawmakers, McConnell has reversed course and now says he will propose an earmark moratorium.

Next you have a Tea Party favorite, Minnesota congresswoman Michele Bachmann, who in reference to earmarks has said, “It’s all bad, as far as I’m concerned … All this pork is bad. The old pork was bad. The new pork is bad.” This from a legislator who has, in the past two years, sent home nearly $4 million in federal earmarks for projects in her district. Not only that, she has reportedly been pushing to have the term earmark redefined to exempt transportation-related projects, which accounts for the overwhelming majority of such funds. She recently told the Minneapolis Star Tribune: “I don’t believe that building roads and bridges and interchanges should be considered an earmark … There’s a big difference between funding a tea pot museum and a bridge over a vital waterway.” But the bottom line is, regardless of what term is used, it’s appropriating someone else’s tax money and redirecting it for the benefit of a particular legislator’s preferences.

Both Tea Party activists and mainstream Republicans achieved a major victory this past Election Day, which many interpreted as a mandate to rein in excessive government spending. According to the Congressional Budget Office, defense spending accounts for the largest share of federal spending (23%) — more than Social Security (20%) or Medicare and Medicaid (19%) — and increased at a 9% annual rate between 2000 and 2009. The willingness expressed by incoming senators Rand Paul, Pat Toomey and Marco Rubio to consider cuts in defense along with other discretionary spending has opened another wound between those preaching fiscal responsibility and those wishing to exempt certain appropriations from the knife. One critic has been Arizona Senator John McCain, himself a decorated Navy veteran, who recently said during a conference at the Foreign Policy Initiative, a DC-based think tank, “I worry a lot about the rise of protectionism and isolationism in the Republican Party.” He then singled out Rand Paul: “I admire his victory, but … already he has talked about withdrawals [and] cuts in defense.”

Oklahoma Republican senator Tom Coburn countered McCain’s charges by saying in The Cable: “It’s not hard to cut the defense budget and keep our defense exactly where it is … That’s how much waste is over there. Nothing is sacrosanct, it can’t be. As a matter of fact, the way the Defense Department is run now, we’re actually getting less bang for the buck. If we trim it down, we’ll get more bang for the buck.” And for her part, former Alaska governor Sarah Palin, in a June 2010 entry on her Facebook page, cited a quotation from current Defense Secretary Robert Gates:

Secretary Gates recently spoke about the future of the US Navy. He said we have to ‘ask whether the nation can really afford a Navy that relies on $3 to $6 billion destroyers, $7 billion submarines, and $11 billion carriers.’ He went on to ask, ‘Do we really need… more strike groups for another 30 years when no other country has more than one?’ Well, my answer is pretty simple: Yes, we can and, yes, we do because we must.

Regardless of which side prevails in this fight — and it will be a fight — the bottom line is that if conservatives are truly serious about getting the federal budget deficit under control, they must realize there are limited means by which to do it. They must take principled stands on defense and earmarks, as they would on any other aspect of federal spending.

Christopher Hartman is the author of “Advance Man: The Life and Times of Harry Hoagland”; editor of “Learn Earn and Return: My Life as a Computer Pioneer,” a memoir of Harlan Anderson, co-founder of Digital Equipment Corporation, and contributor to the Christian Science Monitor newspaper.