What is the single most consequential political development of the past five years? Some might say the election (and re-election) of Barack Obama; others might point to the passage of the most important piece of social policy (Obamacare) since the 1960s; some might even say the drawing down of US wars in Iraq and Afghanistan. But in reality, it is the rapid descent of the Republican party into madness.

Never before in American history have we seen a political party so completely dominated and controlled by its extremist wing; and never before have we seen a political party that brings together the attributes of nihilism, heartlessness, radicalism and naked partisanship quite like the modern GOP. In a two-party system like America's, the result is unprecedented dysfunction.

Whether it was the promiscuous use of the filibuster and other blocking techniques in the Senate to stop President Obama's agenda; the manufactured fiscal crises highlighted by the disastrous debt limit showdown of 2011; or the unceasing efforts to undermine the economic recovery by blocking any and all measures to stimulate the economy, President Obama's first term was dominated by the Republican's unbridled obstructionism and disinterest in actually governing the country. That anything was accomplished is nothing short of a miracle.

But after the results of the 2012 election one might have expected the Republican fever to break and some level of sanity and good sense restored to the party of Lincoln.

Think again.

If anything, the first half of 2013 has seen the GOP continue its journey towards "peak awful". Go back to the beginning of the year. As millions of Americans were celebrating New Year's Eve, the Republicans were careening the country off the fiscal cliff because of their insistence that no rich person should ever pay a cent in higher taxes. The budgetary mania continued through the sequestration and refusal to compromise with President Obama even after he put the liberal sacred cow of Social Security on the table. Along the way Republicans foiled modest efforts at gun control, ginned up made-up scandals involving the IRS and the death of four Americans in Benghazi and couldn't actually be bothered with the difficult task of proposing public policy legislation. And after three years of complaining incessantly that Senate Democrats haven't passed a budget, key Republicans have spent the last 100 days obstructing the budget process.

But in the past few weeks things have actually gone from terrible to unimaginable. There's the GOP "Ebenezer Scrooge" Farm Bill, which would have cut food stamps by $20.5bn, causing nearly 2 million poor Americans to lose food assistance. As if that wasn't bad enough, the Republican House also passed an amendment to the bill that would force food stamp recipients to work in return for benefits, but provided no actual funds for job training. In fact, it even barred states from spending more money on employment and training. So if you're a poor person and you lose your job, you lose the government benefits that allow you to feed you family. This piece of monstrous legislative cruelty was supported by all but six House Republicans. Thankfully the larger bill failed, but Republican heartlessness has hardly been dimmed.

Across red state America, Republican legislators are doubling down on new abortion restrictions like those soon to become law in Wisconsin that would force women who want a constitutionally protected abortion to have, in some cases, a wand inserted into their vagina so they can see the fetus they are about to abort. In Ohio, the state recently enacted new anti-abortion laws that not only divert federal funds away from Planned Parenthood to anti-abortion "crisis pregnancy centers" where women are fed a witches brew of mistruths about the health risks of abortion.

Perhaps the worst case is in Texas, where a proposed law would ban any abortion after 20 weeks and allow precious few exceptions for the health of the mother or the condition of the fetus. So imagine if a woman goes in to see her doctor in the 21st week of her pregnancy and discovers that her baby is afflicted with a genetic anomaly. This is not a hypothetical since procedures like an amniocentesis are performed in the later stages of pregnancy and can detect such disorders. Under the Texas law, a woman would be forced to carry that baby to term. This is akin to state-sanctioned torture. And even if the woman's health were partially, but not severely at risk, abortions would be forbidden. Amazingly, this ban is actually more generous than the recent post-20 week abortion ban passed in the House of Representatives, which would have no exceptions except in the case of the life of the woman.

Texas legislators and Governor Rick Perry have defended these bans as part of their fierce regard and respect for human life. Unfortunately, that pro-life agenda is all too rarely applied to non-fetuses. For example, Texas also has one of the paltriest welfare programs in the US (recipients get less than $300 a month). The state has also consistently refused to take federal money to expand health insurance for children and Texas has joined two dozen other red states in refusing to take federal money to expand Medicaid for its poorest citizens.

The GOP's efforts to reject Medicaid expansion (which is a crucial part of Obamacare) are perhaps the best example of the Republican party's achievement of "peak awful". Even though under the provisions of the law the federal government would be picking up the tab for the first five years of the program and even though Republican governors like Rick Scott in Florida, Rick Snyder in Michigan and John Kasich in Ohio support the expansion, GOP legislators are balking. They plead fiscal rectitude as the root of their opposition (a fallacious claim) but in reality the opposition is yet another example of Republican psychosis about Obamacare. The decision to reject Medicaid money will not only increase the economic anxiety of potential recipients, it will harm mental health and literally cost lives. But such "humane" arguments have done little to shake GOP intransigence.

Indeed, Republicans on the national level are now doing everything in their power to ensure Obamacare fails. Just this past week, key GOP senators, after discovering that the Obama administration was working with major sports leagues to encourage people to sign up for coverage, wrote a stern letter threatening the leagues for partnering with the White House on a law that was passed along partisan lines and is "controversial". Hmm, wonder how that happened?

Now let's put aside for a second that Obamacare was passed by Congress and upheld by the US supreme court. Even if Republicans remain unhappy with the legislation it is the law of the land and its proper implementation is the responsibility of the federal government. But the GOP goal is not to make sure even what they believe to be a terribly flawed law works; it's to make sure it fails so that Democrats will be blamed and Republicans will reap the political benefit. That millions of Americans will be harmed and will suffer because of this narrow political agenda seems to be of little concern.

Then again, none of this should be a surprise to even sentient observers of American politics. In the narrow pursuit of political gain, Republicans have adopted an agenda that is quite simply, inhumane and cruel. Even if one is charitable and defends it on the ground of adherence to an ideological agenda of smaller, less intrusive government (except in the case of lady parts) it can't be defended. If one's ideological predisposition means denying food assistance to people who are laid off from their job or forcing a woman to carry a dead fetus to term or preventing individuals from getting health care coverage, then you have a monstrous ideology.

This is not meant as an indictment of all Republicans because it's very likely that many rank and file Republicans don't share these predispositions (though clearly some do). Rather it's an indictment of a once proud political party that is plumbing the depths of radicalism and nihilism and doesn't yet appear to have hit rock bottom.