If you heard of Croatia, chances are it was either war, sports or tourism. War is fortunately a fading memory in Zagreb, the nation's capital. Being far enough from the frontlines, Zagreb wasn't attacked much during the war anyway - an exception being the 1995 missile attack that hit the town centre, including the national theatre and a children hospital. No, we don't like the Serbs much. As for the Americans, we liked you because the Clinton administration was in favour of us. Years passed since then and you elected Bush (twice!?), so our opinion degraded. But it's still better than average.
Zagreb is again a convenient middle-European city with decent public transport decent and safe streets. There aren't any parts of the town that are considered dangerous after dark or anything like that. There is a small random chance you get beaten up for being black or gay or similar preposterous behavior, but you won't get mugged.
These summer days Zagreb has nothing to offer except high prices. Every, and I do mean every Zagrep can will do whatever possible to escape crippling heat and go to the seaside. Those few people you meet here between mid-July and mid-August won't have anything other on their mind. If you want to visit Zagreb, late spring would be ideal, with the town centre rich with street performers, musicians and people in general. Even then, truth be told, you'd be better off visiting Croatian islands and coastal towns. Zagreb is all right, but why settle for all right if you can go to Dubrovnik or Hvar?
If you do come, Zagreb can show you beautiful old graveyard Mirogoj, some nice parts of the old town, and the life of the city centre. Most of it comes down to cafes. Sitting in cafes, walking from one café to another, walking by cafes looking at people sitting there… It's the national, often criticized, pastime. Seeing all those cafes packed with people during working hours, one has to wonder what kind of jobs those people have. And if they're unemployed (unemployment being another major pastime), shouldn't they be doing something better than spending money on drinks and cigarettes, while sitting and complaining? Wherever in Zagreb you are, there is a café or a bar in the immediate vicinity.
This relaxed approach to work provokes mixed reaction from foreigners living here - some can't get accustomed to the fact that it's normal to be 10 minutes late, while others welcome it. My English colleague chose Zagreb over London as a place to live to get away from the big city rush. At the same time, people from Split (the second largest Croatian city, Zagreb's coastal counterpart) can't stand Zagreb's business-mindedness and fast pace. In Split people will tolerate being 20 minutes late, and on the islands it's all right as long as you come the same day.
I like Zagreb because it's big enough that you can meet new people every time you go out and small enough that you can get around on a bicycle. We are also a convenient 2-hours drive from the Croatian coast, from Austria, Italy, Hungary or Bosnia. And the girls are pretty!