As an urban planner, I will be the first to admit that we are all - myself and my fellow urban planners together - waging an aggressive and vindictive war against cars.
Our rationale is robust: equal parts ethos, pathos, and logos. On ethical grounds, resisting cars' destructiveness on the atmosphere is simply the right thing to do. On an emotional level, cars have conquered the streets that once belonged to us, relegating us to second-class species, and it's time to take them back! And logically, more mass transit and less private cars would be a more efficient use of both energy and land.
At first glance, the battlefield appears laden with explosives, traps, and other obstacles. Retrofitting systems of neighborhood-choking highways and boulevards into walkable environments fit for human street life sounds good, but who's paying for it? And how long will these reconstructions take? And how do you know that these traffic "improvements" will actually improve traffic conditions, or invigorate street life as advertised?
Worries, worries, worries. Excuses, excuses, excuses.
First, let's address the cost. Fortunately, the weapons we need for our war against cars are cheap. All we need is some goddamn paint and some goddamn cones. (Planters also work as a more aesthetically pleasing, if slightly less cheap, alternative to cones). Take a four-lane avenue, paint two, sprinkle in some cones strategically, and you've got any number of traffic improvements: dedicated bus lanes; parking-protected bike lanes; extended sidewalks for outdoor seating; space for bus shelters or food trucks; and so on.
Second, it's far quicker to retrofit streets with paint and cones than it is to widen a street with all those construction trucks and shit.
And finally, if the paint and cones don't work as planned, we can repaint the street in question and move the cones around until we get it right. Sadly, you can't unpave every road you want to take back from cars. But you can repaint them.
So what is your local government's excuse?